Warn Dual Battery Control Kit

Lets you use two batteries, but saves the main battery for essential functions, such as starting the vehicle.
Engineered specifically to give maximum power during winch power-in operation.
For use with 12-volt accessories such as winches, lights, stereos and more.
Minimizes charging system overload; if both batteries need charging, the main battery is charged first.
Optional manual override forces a parallel connection when you need extra power for charging a weak battery or jump-starting another vehicle.
Designed for use with 12-volt DC magneto or alternator charging systems.
Easy to install; includes all necessary hardware. (Second battery not included)
Compatible with LeadAcid batteries only