The Circuit Boss dual battery control system provides you with control over your vehicles charging system. A three position switch enables different power combinations for maximum power while starting, winching, etc. Minimal alterations are necessary to the stock charging system which functions normally after the Circuit Boss has been installed. The standard dual battery control is good for most applications. Painless' waterproof system uses military spec switches for heavy duty automotive use. Kits include: solenoid, switch, preteminated wire/connectors, fuse holder, fuse and mounting hardware. *Does not include battery cables for connecting your dual battery setup. This is the waterproof dual battery control system and solenoids are rated at 250 amps.