Goodall 12/24V Commercial Heavy-Duty AntiZap Surge Protector with 12' cable, is designed for passenger cars, buses, marine vessels, heavy industry, and agriculture, with a heavy-duty, weatherproof and shockproof housing. The Goodall Surge Protector mounts to the side of the vehicle battery or bodywork, with the unit connected to the negative and positive battery terminals. Once this is in place, the vehicle's original electronic accessories are protected from on-board or externally-generated voltage spikes. The Goodall Surge Protector also features crimped, tin-plated, heavy-gauge, solid copper lugs and provides full-time electronic surge protection.