Using a Hardkorr battery box with voltage-sensitive relay (VSR) is the simplest way to create a dual battery setup in your vehicle. The VSR acts as an isolator, allowing the auxiliary battery (inside the box) to charge directly from the crank battery while the car is running.
Using a Hardkorr battery box with voltage-sensitive relay (VSR) is the simplest way to create a dual battery setup in your vehicle. The VSR acts as an isolator, allowing the auxiliary battery (inside the box) to charge directly from the crank battery while the car is running.
Korr Voltage-Sensitive Relay Kit for Hardkorr Battery Box
Using a Hardkorr battery box with voltage-sensitive relay (VSR) is the simplest way to create a dual battery setup in your vehicle. The VSR acts as an isolator, allowing the auxiliary battery (inside the box) to charge directly from the crank battery while the car is running.
Using a Hardkorr battery box with voltage-sensitive relay (VSR) is the simplest way to create a dual battery setup in your vehicle. The VSR acts as an isolator, allowing the auxiliary battery (inside the box) to charge directly from the crank battery while the car is running.
in 14 offers
The lowest price for Korr Voltage-Sensitive Relay Kit for Hardkorr Battery Box right now is $35.00 at Superior Engineering, compared across 14 retailers.
The all-time low was $27.99 on 27 Nov 2025 — today's price is 25% above the lowest ever. It has been notably cheaper before — worth setting a price alert.
Prices last updated 8 June 2026.
Last updated at 08/06/2026 22:56:03
HARDKORR Voltage-Sensitive Relay (VSR) for Battery Box (Each) - HKPBATTVSR
Delivery $46.39
Hardkorr HKPBATTVSR Voltage Sensitive Relay VSR Kit For Battery Box
Next-day delivery $28.99
Hardkorr HKPBATTVSR Voltage Sensitive Relay VSR Kit For Battery Box
Next-day delivery $19.99
Hardkorr Voltage Sensitive Relay Kit for Heavy Duty Battery Box
Delivery between Wed – Mon $12
Hardkorr HKPBATTVSR Voltage Sensitive Relay suit Battery Box
Delivery $20
HARDKORR VOLTAGE SENSITIVE RELAY KIT
Delivery between 11–17 June $9.95
Voltage-Sensitive Relay Kit (can be used with Hardkorr Battery Box)
Delivery between 12–17 June $8.73
Hardkorr Voltage -Sensitive Relay Kit
Delivery $18
Hard Korr Voltage Sensitive Relay (Vsr) Kit For Hard Korr Battery Box
HARDKORR VOLTAGE SENSITIVE RELAY KIT
Delivery between 11–17 June $0
originally posted on bcf.com.au
Great hi power switching for new vehicles. Needed high amperage from starter battery for caravan/camper power plug & with complex new vehicle wiring, the VSR was the easy choice to have the power turn on after 4x4 starts up & when stopped VSR turns power off in a minute. Easy to fit if you can do your own wiring.
originally posted on bcf.com.au
Not as beefy as some other brands, but seems to work fine and was easy to install. It's small size makes it easy to hide away.
originally posted on bcf.com.au
Better pictures of how to install would be better. First time doing anything like this so pictures or better instructions would have made it easier. But in the end I was able to install it correctly. Get little product for battery boxes as I use mine for a dual battery setup in my ute.
| Voltage | 12V DC |
| Cut-in voltage | 13.2V |
| Cut-out voltage | 12.8V |
| Standby draw | 10mA |
| Delay | 15 sec |
HARDKORR Voltage-Sensitive Relay (VSR) for Battery Box (Each) - HKPBATTVSR
Delivery $46.39
Hardkorr HKPBATTVSR Voltage Sensitive Relay VSR Kit For Battery Box
Next-day delivery $28.99
Hardkorr HKPBATTVSR Voltage Sensitive Relay VSR Kit For Battery Box
Next-day delivery $19.99
Hardkorr Voltage Sensitive Relay Kit for Heavy Duty Battery Box
Delivery between Wed – Mon $12
Hardkorr HKPBATTVSR Voltage Sensitive Relay suit Battery Box
Delivery $20
Great hi power switching for new vehicles. Needed high amperage from starter battery for caravan/camper power plug & with complex new vehicle wiring, the VSR was the easy choice to have the power turn on after 4x4 starts up & when stopped VSR turns power off in a minute. Easy to fit if you can do your own wiring.
Not as beefy as some other brands, but seems to work fine and was easy to install. It's small size makes it easy to hide away.
Better pictures of how to install would be better. First time doing anything like this so pictures or better instructions would have made it easier. But in the end I was able to install it correctly. Get little product for battery boxes as I use mine for a dual battery setup in my ute.
Easy enough to install. Though it was a little difficult to get the VSR in position with all the wiring in the way, I was able to gently lift the wires over the top of the VSR as pictured and work around them. Took 15 mins with a 12mm & a 10mm socket/wrench (if I remember correct) and a small Phillips head. Stoked to have also bought one of Hard Korr’s solar panels.. their products make for an easy to configure and reliable 12v system.
fantastic
Works perfectly with the hardkorr batery box, have had absolutely no issues
Very easy to install into the battery box. Great price too.
| Voltage | 12V DC |
| Cut-in voltage | 13.2V |
| Cut-out voltage | 12.8V |
| Standby draw | 10mA |
| Delay | 15 sec |
