Surface Mount, install the circuit breaker on your boat, connect one end to the engine and the other end to your battery box. All the wires and circuit breakers can be assembled very easily. The circuit breaker can be manually disconnected, manually reset, very convenient, Stops Power Surges From Damaging Your Amps to protect your gear [Special tips] Ideal for car audio and video systems, boats, trucks, buses, RVs, ATV, marine, and DC sound amplifier system overload protection. [Size]60A, 3.9in L x 1.65in W x 1.57in H Red manual reset button, with 2 install screws in package. compatible with all 12V48VDC Systems [Safe and Conveniency] Type 3 manual resettable make sure to protect your appliance in an overcurrent or short circuit condition. A red button can serve as a master disconnect. we also provided you with two screws to help you install [Widely Application] High amp circuit breakers are used as the main power protection for all circuits coming off your battery [Optimal Design] High amperage circuit breakers provide current protection in a compact package, Good Conductivity, Temperature And Pressure Resistance, Splash and dustproof [High Quality] Manufactured by M1A2, these circuit breakers set the standard in highpower DC circuit protection.They conform to SAE J162S; SAE J1171 ignition protected standard