Will operate 12 volt negative ground accessories from 6,8 or 12 volt positive ground electrical systems. When used in a 6 volt positive ground system, it can continuously supply more than 2.1 amps with the engine off, and about 2.5 amps with the engine running at a fast idle. In a 12 volt positive ground system it can supply 4.0 amps (min) and 4.7 amps (max) continuous duty. The PGPI-HC uses a common ground so isolation is not necessary, and because of its efficient design, its current draw is negligible when no load is applied (10 milliamps). NOT RECOMMENDED FOR: Power actuated door locks, trunk release solenoids, air conditioner clutches, fans, blowers, power windows, or other electromechanical devices.