I have an Alpine 1400 Watt RMS system in a boat connected to an Isolated Kinetic 2400 Battery. I wanted lots of battery time so the boat could just sit and play without worries. Well the boat rocks. I only have a 55 amp alternator and have not upgraded the main battery wiring. Yes I have a monster battery isolated from the main system by manual switch. I have let the boat sit with the stereo cranked full volume for 6+ hours at a time. Frankly I have never yet drained the Kinetic when doing this. I have this Cap inline in the power very close to the Alpine PDX-1.600 that pushes the Alpine Type R sub. The Cap has a volt meter on it that is very useful and a little light that lights every time the Cap is handling the power deficiency. It works great. I have seen this system drop to 11.4 Volts and still pound hard due to this Cap. As my Kinetic battery starts to drop in voltage this cap goes to work and the Sub-Woofer is never even affected by it. The whole set up works beautifully and this Cap does its job perfectly. Very Happy with the results of this system.