I've just ordered a couple of these to supplement my car audio in a '34 hotrod. These were the only ones that would fit in the tight area of my hotrod interior. I've got 2 amps...a 600 watt stereo and a 2000 watt sub amp...(Hifonics) running off these. They work much better than caps and really help the system. I will definitely be ordering more for my other vehicles. Other brands don't offer the various sizes these guys do and the prices rock...Go Kinetik's!!!!