Profile: National Fuse Products is mainly engaged in providing electrical fuses, circuit protection, circuit breakers, and fuse blocks. We carry a wide variety of both conventional and semiconductor style circuit breakers to meet circuit protection needs. We specialize in obsolete or hard-to-find replacement circuit breakers for industrial and commercial applications. Our fuse uses a calibrated current-carrying element to control the current passing through the system. If the current applied to the fuse generates enough heat to exceed the melting point of the fuse element, the fuse will open or break the circuit.