Details Casio G-Shock G-Steel Watch GST-B100D-1A offers ultimate toughness and chronograph performance in analog format. It features a new layer guard structure houses resin cushioning parts inside the case for more elegant design and a better fit to the wrist. The watch comes equipped with Bluetooth that lets them connect with a smartphone at the press of a button and acquire time information from an internet time server. This G-Shock series watch is 200-meter water resistant and also has shock resistant construction with mineral front glass. Other specs of the watch are Solar powered, LED light (Super Illuminator), Date display, Day indicator, Battery level indicator, New layer guard structure and 5 months battery life on rechargeable battery. Specs Case / bezel material: Resin / Stainless steel One-touch 3-fold Clasp Solid Band Stainless Steel Band Shock Resistant Neobrite Mineral Glass Screw Lock Crown 200-meter water resistance Solar powered LED light (Super Illuminator) Afterglow Mobile link (Wireless linking using Bluetooth ) Dual time (Home city time swapping) 1-second stopwatch Measuring capacity: 23:59'59 Measuring mode: split time Countdown timer Measuring unit: 1 second Countdown range: 24 hours Countdown start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments) Daily alarm Battery level indicator Power Saving (hands stop to save power when the watch is left in the dark) Full auto-calendar (to year 2099) Date display Day indicator Regular timekeeping Analog: 3 hands (hour, minute (hand moves every 10 seconds), second), 3 dials (dual time hour and minute, dual time 24-hour, day) Accuracy: ±15 seconds per month (with no mobile link function) Approx. battery operating time: 5 months on rechargeable battery (operation period with normal use without exposure to light after charge) 24 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge) Size of case : 58.1×53.8×14.1mm Total weight : 185g