Stinger SGP38 SGP Series 80-Amp Relay and IsolatorStinger SGP38 SGP Series 80 Amp Relay and Isolator 80 amps constant, 150A amps peak; Compatible with all types of alternators and charging systems; Prevents primary battery discharge ; Maximum current transfer; Ideal for second audio battery isolation from vehicle systems; Water resistant black phenolic plastic; 100,000 mechanical cycle life;