Battery switch with waterproof cover 100A Perfect for any type of installation on a 12 or 24 V electrical circuit with battery, this box with integrated circuit breaker will fit perfectly on your boat or converted van. The circuit breaker, or battery isolator, is an essential part of any 12V or 24V battery electrical system. Whether on a sailboat, motorhome or converted van, it's essential to install a quality circuit breaker to secure the entire installation. There are a number of clever models that incorporate a battery isolator in a plastic box with a splash-proof hatch. The flush-mounted box, made from UV-resistant plastic, can be installed inside or outside the RIB's cockpit. A key makes it easy to open and close the distribution circuit.