Perko 250 Amp Battery Disconnect Switch for 12, 24 or 36 Volt Systems Designed for surface mounting, the Perko Battery Disconnect Switch has a bright red polycarbonate housing with a large easy-to-turn black knob. The Perko Battery Disconnect Switch helps manage the overall use of electrical power on board. This device allows for a quick and easy way to shut down the entire electrical system in an emergency. During inactivity, the Perko battery Disconnect Switch will help prevent battery drain.