Casio Watch G-Shock GA-2100-1A2ER - Casio
Uncompromising Strength Meets Sophisticated Design Experience the perfect blend of style, functionality, and durability with the G-Shock CasiOak Carbon Core Guard GA2100-1A1. As an illustrious heir of the original DW-5000C introduced in 1983, this watch evokes G-SHOCK’s timeless appeal while pushing the boundaries of resilience. Signature Octagonal Form This model sports the unique octagonal shape reminiscent of the pioneering DW-5000C. The classic analog-digital timekeeping is seamlessly integrated into a straightforward, clutter-free design, without compromising the iconic G-SHOCK toughness. Thin Yet Robust With the high-strength resin material reinforced with carbon fibers, this watch boasts an impressively thin case. At just 11.8 mm, it stands as the thinnest among G-SHOCK combination models, offering a sleek profile without sacrificing robustness. Featuring the exclusive Neobrite technology, the GA-2100-1A and GA-2100-4A models deliver enhanced visibility in low-light conditions. Carbon Core Guard Structure The innovative carbon core guard structure provides advanced protection to the module. By enclosing it in a carbon case, the watch gains exceptional strength, crack resistance, and durability. This case is constructed with fine resin infused with carbon fibers, affirming the watch's commitment to enduring toughness.
Uncompromising Strength Meets Sophisticated Design Experience the perfect blend of style, functionality, and durability with the G-Shock CasiOak Carbon Core Guard GA2100-1A1. As an illustrious heir of the original DW-5000C introduced in 1983, this watch evokes G-SHOCK’s timeless appeal while pushing the boundaries of resilience. Signature Octagonal Form This model sports the unique octagonal shape reminiscent of the pioneering DW-5000C. The classic analog-digital timekeeping is seamlessly integrated into a straightforward, clutter-free design, without compromising the iconic G-SHOCK toughness. Thin Yet Robust With the high-strength resin material reinforced with carbon fibers, this watch boasts an impressively thin case. At just 11.8 mm, it stands as the thinnest among G-SHOCK combination models, offering a sleek profile without sacrificing robustness. Featuring the exclusive Neobrite technology, the GA-2100-1A and GA-2100-4A models deliver enhanced visibility in low-light conditions. Carbon Core Guard Structure The innovative carbon core guard structure provides advanced protection to the module. By enclosing it in a carbon case, the watch gains exceptional strength, crack resistance, and durability. This case is constructed with fine resin infused with carbon fibers, affirming the watch's commitment to enduring toughness.
Uncompromising Strength Meets Sophisticated Design Experience the perfect blend of style, functionality, and durability with the G-Shock CasiOak Carbon Core Guard GA2100-1A1. As an illustrious heir of the original DW-5000C introduced in 1983, this watch evokes G-SHOCK’s timeless appeal while pushing the boundaries of resilience. Signature Octagonal Form This model sports the unique octagonal shape reminiscent of the pioneering DW-5000C. The classic analog-digital timekeeping is seamlessly integrated into a straightforward, clutter-free design, without compromising the iconic G-SHOCK toughness. Thin Yet Robust With the high-strength resin material reinforced with carbon fibers, this watch boasts an impressively thin case. At just 11.8 mm, it stands as the thinnest among G-SHOCK combination models, offering a sleek profile without sacrificing robustness. Featuring the exclusive Neobrite technology, the GA-2100-1A and GA-2100-4A models deliver enhanced visibility in low-light conditions. Carbon Core Guard Structure The innovative carbon core guard structure provides advanced protection to the module. By enclosing it in a carbon case, the watch gains exceptional strength, crack resistance, and durability. This case is constructed with fine resin infused with carbon fibers, affirming the watch's commitment to enduring toughness.
Uncompromising Strength Meets Sophisticated Design Experience the perfect blend of style, functionality, and durability with the G-Shock CasiOak Carbon Core Guard GA2100-1A1. As an illustrious heir of the original DW-5000C introduced in 1983, this watch evokes G-SHOCK’s timeless appeal while pushing the boundaries of resilience. Signature Octagonal Form This model sports the unique octagonal shape reminiscent of the pioneering DW-5000C. The classic analog-digital timekeeping is seamlessly integrated into a straightforward, clutter-free design, without compromising the iconic G-SHOCK toughness. Thin Yet Robust With the high-strength resin material reinforced with carbon fibers, this watch boasts an impressively thin case. At just 11.8 mm, it stands as the thinnest among G-SHOCK combination models, offering a sleek profile without sacrificing robustness. Featuring the exclusive Neobrite technology, the GA-2100-1A and GA-2100-4A models deliver enhanced visibility in low-light conditions. Carbon Core Guard Structure The innovative carbon core guard structure provides advanced protection to the module. By enclosing it in a carbon case, the watch gains exceptional strength, crack resistance, and durability. This case is constructed with fine resin infused with carbon fibers, affirming the watch's commitment to enduring toughness.
in 38 offers
The lowest price for Casio Watch G-Shock GA-2100-1A2ER - Casio right now is $140.25 at Iguana Sell AU, compared across 19 retailers.
The all-time low was $83.00 on 31 Dec 2025 — today's price is 69% above the lowest ever. It has been notably cheaper before — worth setting a price alert.
Prices last updated 13 Aug 2026.
Last updated at 13/08/2026 10:25:14
G-SHOCK Men's Analog-Digital Watch
Free delivery
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G-SHOCK Casio Classic Quartz Watch, Resin, Black, 55 × 51.2mm, GA-2100-1A3ER
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G-SHOCK Casio Classic Quartz Watch, Resin, Black, 48.5 × 45.4mm, GA-2100-1A4ER
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G-SHOCK Casio Classic Quartz Watch, Resin, Black, 48.5 × 45.4mm, GA-2100-1A2ER
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originally posted on g-shock.co.uk
I like the looks, functionality and robustness of the GA-B2100. The Tough Solar and Bluetooth seemed interesting new features over the original GA-2100 and tempted me to buy one.I set up my watch and noticed the battery indicator dipped from ‘f’ to ‘m’. Rather than wear the watch I decided to leave it on a south facing window sill to recharge thinking that it would only need a short burst of sun to top up to ‘f’ again. In the evening it sat by a light bulb. Six days later it was still on ‘m’. I returned it to Casio who have been great to deal with.I am expecting a replacement soon. Hopefully my experience was a one off. My local Casio dealer said they hadn’t had any experience of this issue before. I have a suspicion the Bluetooth and tough Solar combo can’t ... MoreI like the looks, functionality and robustness of the GA-B2100. The Tough Solar and Bluetooth seemed interesting new features over the original GA-2100 and tempted me to buy one.I set up my watch and noticed the battery indicator dipped from ‘f’ to ‘m’. Rather than wear the watch I decided to leave it on a south facing window sill to recharge thinking that it would only need a short burst of sun to top up to ‘f’ again. In the evening it sat by a light bulb. Six days later it was still on ‘m’. I returned it to Casio who have been great to deal with.I am expecting a replacement soon. Hopefully my experience was a one off. My local Casio dealer said they hadn’t had any experience of this issue before. I have a suspicion the Bluetooth and tough Solar combo can’t contend with a British winter. I hope my doubts are dispelled by my replacement watch. My digital Tough Solar watch seems fine with murky winter light.
originally posted on g-shock.co.uk
GA-2100-5AERFantastic Casio G-Shock,By my favourite watch maker,excellent specs on this beautiful watch : time, world time, stop watch, countdown timer, light, dual analogue & digital display.Nifty features : press two buttons & the analogue hands move away from the digital display. The digital display can display the month, day, running seconds or time & running seconds. The light can display between one & three seconds.The analogue display : hours, minutes & day of the week. Hands are lume filled.Comfortable fit, lightweight, good wrist presence. Nice "caramac" colour. The watch is really impact resistant - it's a G-Shock & has water resistance to 200m.Who is this for? People who may travel - world time. Sporty people - stopwatch & countdown timer. Young ... MoreGA-2100-5AERFantastic Casio G-Shock,By my favourite watch maker,excellent specs on this beautiful watch : time, world time, stop watch, countdown timer, light, dual analogue & digital display.Nifty features : press two buttons & the analogue hands move away from the digital display. The digital display can display the month, day, running seconds or time & running seconds. The light can display between one & three seconds.The analogue display : hours, minutes & day of the week. Hands are lume filled.Comfortable fit, lightweight, good wrist presence. Nice "caramac" colour. The watch is really impact resistant - it's a G-Shock & has water resistance to 200m.Who is this for? People who may travel - world time. Sporty people - stopwatch & countdown timer. Young people - G-Shock have great appeal. People who want a watch that is tough, light & feature filled.There are opportunities to mod your watch with new buckles, bullbars or metal kits.A G-Shock is a no brainer, I have at least eight.Totally recommended.
originally posted on g-shock.co.uk
Really good watch. Straight out the box very pleased.The hands are a lot easier for seeing rather than the all black which I had previously, also a fantastic watch.The date area is very difficult to read which is a let down. They should have used a lighter background rather than the negative. You can move the hands by pressing the light and "Mode" which moves the hands should they obscure the date area, then you can simply move them back.The glow in the dark is really good and you can give it a quick charge by a lightbulb or natural light which lasts all night. Very readable in the dark.The wristband is comfortable and the whole thing simply works as it should do. I wear mine literally 24/7 it rarely leaves my wrist.The days of the week is much better to see ... MoreReally good watch. Straight out the box very pleased.The hands are a lot easier for seeing rather than the all black which I had previously, also a fantastic watch.The date area is very difficult to read which is a let down. They should have used a lighter background rather than the negative. You can move the hands by pressing the light and "Mode" which moves the hands should they obscure the date area, then you can simply move them back.The glow in the dark is really good and you can give it a quick charge by a lightbulb or natural light which lasts all night. Very readable in the dark.The wristband is comfortable and the whole thing simply works as it should do. I wear mine literally 24/7 it rarely leaves my wrist.The days of the week is much better to see with the fluorescent giving it a natural glow which stands out nicely but not too much.I've worn this in the bath, the beach, the sea, freezing winter and it holds up as its advertised.A+ once again G-Shock you've surpassed my expectations.
| Diameter | 45.4 mm |
| Water Resistance | 20 Bar (Dive) |
| Time | hours - Analogue hand |
| Calendar | Date - Digital |
| Chronograph and timers | Stopwatch /Chronograph - 1/100 seconds 24 hours |
G-SHOCK Men's Analog-Digital Watch
Free delivery
Affiliate Disclosure: We may receive a small commission for purchases made through this link at no extra cost to you. This helps support our site. Thank you!
G-SHOCK Casio Classic Quartz Watch, Resin, Black, 55 × 51.2mm, GA-2100-1A3ER
Delivery $59
G-SHOCK Casio Classic Quartz Watch, Resin, Black, 48.5 × 45.4mm, GA-2100-1A1ER
Delivery $59
G-SHOCK Casio Classic Quartz Watch, Resin, Black, 48.5 × 45.4mm, GA-2100-1A4ER
Delivery $59
G-SHOCK Casio Classic Quartz Watch, Resin, Black, 48.5 × 45.4mm, GA-2100-1A2ER
Delivery $59
I like the looks, functionality and robustness of the GA-B2100. The Tough Solar and Bluetooth seemed interesting new features over the original GA-2100 and tempted me to buy one.I set up my watch and noticed the battery indicator dipped from ‘f’ to ‘m’. Rather than wear the watch I decided to leave it on a south facing window sill to recharge thinking that it would only need a short burst of sun to top up to ‘f’ again. In the evening it sat by a light bulb. Six days later it was still on ‘m’. I returned it to Casio who have been great to deal with.I am expecting a replacement soon. Hopefully my experience was a one off. My local Casio dealer said they hadn’t had any experience of this issue before. I have a suspicion the Bluetooth and tough Solar combo can’t ... MoreI like the looks, functionality and robustness of the GA-B2100. The Tough Solar and Bluetooth seemed interesting new features over the original GA-2100 and tempted me to buy one.I set up my watch and noticed the battery indicator dipped from ‘f’ to ‘m’. Rather than wear the watch I decided to leave it on a south facing window sill to recharge thinking that it would only need a short burst of sun to top up to ‘f’ again. In the evening it sat by a light bulb. Six days later it was still on ‘m’. I returned it to Casio who have been great to deal with.I am expecting a replacement soon. Hopefully my experience was a one off. My local Casio dealer said they hadn’t had any experience of this issue before. I have a suspicion the Bluetooth and tough Solar combo can’t contend with a British winter. I hope my doubts are dispelled by my replacement watch. My digital Tough Solar watch seems fine with murky winter light.
GA-2100-5AERFantastic Casio G-Shock,By my favourite watch maker,excellent specs on this beautiful watch : time, world time, stop watch, countdown timer, light, dual analogue & digital display.Nifty features : press two buttons & the analogue hands move away from the digital display. The digital display can display the month, day, running seconds or time & running seconds. The light can display between one & three seconds.The analogue display : hours, minutes & day of the week. Hands are lume filled.Comfortable fit, lightweight, good wrist presence. Nice "caramac" colour. The watch is really impact resistant - it's a G-Shock & has water resistance to 200m.Who is this for? People who may travel - world time. Sporty people - stopwatch & countdown timer. Young ... MoreGA-2100-5AERFantastic Casio G-Shock,By my favourite watch maker,excellent specs on this beautiful watch : time, world time, stop watch, countdown timer, light, dual analogue & digital display.Nifty features : press two buttons & the analogue hands move away from the digital display. The digital display can display the month, day, running seconds or time & running seconds. The light can display between one & three seconds.The analogue display : hours, minutes & day of the week. Hands are lume filled.Comfortable fit, lightweight, good wrist presence. Nice "caramac" colour. The watch is really impact resistant - it's a G-Shock & has water resistance to 200m.Who is this for? People who may travel - world time. Sporty people - stopwatch & countdown timer. Young people - G-Shock have great appeal. People who want a watch that is tough, light & feature filled.There are opportunities to mod your watch with new buckles, bullbars or metal kits.A G-Shock is a no brainer, I have at least eight.Totally recommended.
Really good watch. Straight out the box very pleased.The hands are a lot easier for seeing rather than the all black which I had previously, also a fantastic watch.The date area is very difficult to read which is a let down. They should have used a lighter background rather than the negative. You can move the hands by pressing the light and "Mode" which moves the hands should they obscure the date area, then you can simply move them back.The glow in the dark is really good and you can give it a quick charge by a lightbulb or natural light which lasts all night. Very readable in the dark.The wristband is comfortable and the whole thing simply works as it should do. I wear mine literally 24/7 it rarely leaves my wrist.The days of the week is much better to see ... MoreReally good watch. Straight out the box very pleased.The hands are a lot easier for seeing rather than the all black which I had previously, also a fantastic watch.The date area is very difficult to read which is a let down. They should have used a lighter background rather than the negative. You can move the hands by pressing the light and "Mode" which moves the hands should they obscure the date area, then you can simply move them back.The glow in the dark is really good and you can give it a quick charge by a lightbulb or natural light which lasts all night. Very readable in the dark.The wristband is comfortable and the whole thing simply works as it should do. I wear mine literally 24/7 it rarely leaves my wrist.The days of the week is much better to see with the fluorescent giving it a natural glow which stands out nicely but not too much.I've worn this in the bath, the beach, the sea, freezing winter and it holds up as its advertised.A+ once again G-Shock you've surpassed my expectations.
I bought this watch because I wanted something that I could wear in the garden, whilst washing the car, out jogging or cycling. As it's a G-Shock I can wear this without worrying about knocking it around, getting it dirty or soaking wet. It's also reasonably good looking (for a G-Shock - I usually find them a bit bulky and plasticky) and wears well no matter the occasion. I like the white hands on the black dial, Makes for high legibility. The digital panel though is very hard to read, both in terms of size and because on this version it is a negative display, which with my eyesight I find really hard to see. However, it doesn't bother me as I bought this for the analogue hands and the fact it is a tough G-Shock which can take a bit of a battering!
It does what it says on the tin, it's a perfect working watch. It looks great, it's comfortable and very durable. The only drawback is the lume. The luminescent hands are very dim, and are hard to see is dim conditions, in dark rooms are almost impossible to see, even when the watch has been in the sunlight all day. There is no luminescent markers on the hour markers, so if it's at night, you won't be able to see the time with a quick glance. Luckily however, it comes with a light. Apart from that it's fantastic, and I'm really pleased with it!
It was the best option I could find to replace a lovely classic watch as there was nothing remotely (of quality) anything similar. Nice to have a white face background instead of black but white fingers makes little sense. Thankfully they do stand out reasonable well and amazingly glow really well in the dark. Additionally the light button illuminates averything well and is much better than the normal yellow glow in the bottom corner. The donwside it the light button is not prominant and so difficlut to find.Date and time figures are clear but tiny in size and, when you consider the advanced technical features of Casio watches I don't understand why we have to accept USA date format instead of the UK norm!I do like the quality and sturdiness of Gshock watches but ... MoreIt was the best option I could find to replace a lovely classic watch as there was nothing remotely (of quality) anything similar. Nice to have a white face background instead of black but white fingers makes little sense. Thankfully they do stand out reasonable well and amazingly glow really well in the dark. Additionally the light button illuminates averything well and is much better than the normal yellow glow in the bottom corner. The donwside it the light button is not prominant and so difficlut to find.Date and time figures are clear but tiny in size and, when you consider the advanced technical features of Casio watches I don't understand why we have to accept USA date format instead of the UK norm!I do like the quality and sturdiness of Gshock watches but am flabbergasted as to why Casio think reading the time easily is less important than looking flashy and incredibly cluttered.The only simple, clear faces you seem to do are on bottom end cheap ones. My favourite had this plus a digital display and looked very nice and classy. I do wish you would bring back this model or something similar.Overall I pleased with this watch but as you can tell from my grumbling there is no other form for feedback available.
Entry level steel G-Shock it's what it is. I love the crazy detail of the watch if you look closely. It's a G - Shock so I won't get into the quality of the components etc, instead - I'll share the feelings I have towards it. Call me weird but this is my Monday watch, when I need that little bit of patting on the back (or writst, lol). It goes perfectly with semi casual outfit as well as blends in nicely with sport t-shirts. It's an eye catcher, too. It has a bit of luxurious hint to it despite being a budget timepiece, which is a bonus obviously. In general it is my second G-Shock and I am sure the family will get bigger in time!
Great watch which is extremely light in weight and pretty good features.This was purchased to replace a 15 year old Wavecept whose rubberised casing (not the stainless steel watch or strap itself which was still in very good working order) could not be replaced.I like the Bluetooth function, the 5 alarms and the reminder function. The fact that it is waterproof to 2 atm is great as there is no need to take it off. I’m not too worried about world time.The only 2 reasons that I have not given it a 5 star rating are:1) the nightlight, whilst great that you can change how long it stays on for is positioned at too low an angle to illuminate the entire dial face efficiently and,2) the day/date function does not alternate between day of the week (SAT) and day ... MoreGreat watch which is extremely light in weight and pretty good features.This was purchased to replace a 15 year old Wavecept whose rubberised casing (not the stainless steel watch or strap itself which was still in very good working order) could not be replaced.I like the Bluetooth function, the 5 alarms and the reminder function. The fact that it is waterproof to 2 atm is great as there is no need to take it off. I’m not too worried about world time.The only 2 reasons that I have not given it a 5 star rating are:1) the nightlight, whilst great that you can change how long it stays on for is positioned at too low an angle to illuminate the entire dial face efficiently and,2) the day/date function does not alternate between day of the week (SAT) and day date/month.….both of which were perfect on my Wavecept.
I like the uncomplicated but yet stylish look of this watch. I do like analogue watches with the added benefit of digital LCD alarm setting, stopwatch and timer. The only downside of this watch is that the LED digits are extremely small and dark to see, making it necessary to angle the watch against the ambient light to read them. However, the important part is that the watch keeps superb time and I'm able to wear it when I'm in the water.On another note: thank you to Watch Direct for a superb service. I ordered the watch Thursday around noon, received a message that afternoon to say the watch has been dispatched, received the watch the following Monday - couldn't ask for a better service. Furthermore the purchase price of the watch from Watch Direct was the best I ... MoreI like the uncomplicated but yet stylish look of this watch. I do like analogue watches with the added benefit of digital LCD alarm setting, stopwatch and timer. The only downside of this watch is that the LED digits are extremely small and dark to see, making it necessary to angle the watch against the ambient light to read them. However, the important part is that the watch keeps superb time and I'm able to wear it when I'm in the water.On another note: thank you to Watch Direct for a superb service. I ordered the watch Thursday around noon, received a message that afternoon to say the watch has been dispatched, received the watch the following Monday - couldn't ask for a better service. Furthermore the purchase price of the watch from Watch Direct was the best I could find. I'm happy!
I just received this today. First impressions are that it looks very cool in the all black version. Surprisingly light (I have a couple of other all metal watches so comparing to them it feels light)Strap is comfortable but personally I feel it looks a bit cheap but that is an easy fix with a new strap (and a couple of 16 to 22mm adapters!). I also found the quick release strap pins quite fiddly to put the strap back on. The strap sits at around 45 degrees the watch so getting my big sausage fingers into the quick release part was tricky. Might not be an issue for most people as you won't often be taking the strap on and off.Visibility of the hands is fine in daylight and also in complet darkness as the hands glow enough to see them. It's low light where I ... MoreI just received this today. First impressions are that it looks very cool in the all black version. Surprisingly light (I have a couple of other all metal watches so comparing to them it feels light)Strap is comfortable but personally I feel it looks a bit cheap but that is an easy fix with a new strap (and a couple of 16 to 22mm adapters!). I also found the quick release strap pins quite fiddly to put the strap back on. The strap sits at around 45 degrees the watch so getting my big sausage fingers into the quick release part was tricky. Might not be an issue for most people as you won't often be taking the strap on and off.Visibility of the hands is fine in daylight and also in complet darkness as the hands glow enough to see them. It's low light where I struggle to see what time it is. The light feature looks cool as it lights up the face but I've noticed already that it lights up the edges of the led screen which can look a little like the hands making seeing the time confusing. The LED screen itself I find too small to see what is there (maybe because the inverted led hasn't enough contrast or my eyesight ain't what it used to be). That said I don't think I would ever use the features on the screen so it doesn't bother me too much.Set up with the app is cool and it was great to see the time adjusting automatically, but again a lot of features I most likely wont use.I sound like I am being negative but for what I bought this watch I am more than happy with its looks. And can put up with the foibles. I wanted a reasonably priced tough watch for everyday knocking around the garden and holidays when I can sweat, swim,get caught in rain etc and not worry about it, without it looking like a throwback from the 80s. Only had a it a few hours so can't comment on its solar charging and battery life but it was in the "low" range out of box and I put it straight on around 6h ago and have been inside that whole time and not even a bright day here? It's now saying "high" charge.All in all I would say if you plan on wearing this as your main watch and will be wearing in low light situations or the features that are displayed on the small screen are important (and your eyesight isn't the best!) Then I would recommend one of the other colour options.For my usage I think it looks pretty awesome and it's cheap enough that I may still buy one or !ore in different colours.
| Diameter | 45.4 mm |
| Water Resistance | 20 Bar (Dive) |
| Time | hours - Analogue hand |
| Calendar | Date - Digital |
| Chronograph and timers | Stopwatch /Chronograph - 1/100 seconds 24 hours |
