PAC PAC-500 500-Amp Relay Battery Isolator 500 AMP Relay/Battery Isolator Used to isolate a second battery powering audio, visual navigation, or other equipment.Does not create a voltage drop to the second battery like conventional isolate Prevents the equipment from discharging the main battery when it is operated while the engine is off Extends battery life Handles 500 amps continuous and 700 amp surges Used to isolate a second battery powering audio, visual navigation, or other equipment Useful for completely isolating equipment from power when off The coil will operate safely up to 16.5-volts Draws Less Than 1-Amp When On Extends battery life