I was going to use this in my sister's car stereo system, but had to install it to her fans instead since her a/c went out 2 days before the product showed up. anyway, I am very pleased because both fans work fine, and no power drainage issues. great for any amplifier or fans that have an 80 amp draw. just make sure you fuse the positive line to the battery or batteries. oh, mine didn't come with markings for the two smaller posts so had to get diagram from a stinger isolater of same style. great for the price though... will buy again once i jump on these re amps for my sis's car (overhauling the system). A+