Nothing stops short circuits like a shortstop circuit breaker. With a 40 amp current capacity, this bussmann Automotive circuit breaker is suitable for demanding loads such such as amplifiers, inverters, generators, Beacons, flood lights, and more. In these higher current demanding electrical applications, having a form of over current and short circuit protection is critical to to prevent catastrophic electrical failure and possible fire. Shortstop circuit breakers are designed to to mainly protect from direct short to ground. They are thermally operated, which means that as more current flows through the circuit breaker, the contacts heat up and we'll eventually separate. In a direct short to ground, this causes the contacts to separate almost immediately. However, in the event of an overcurrent situation where 50 amps might be flowing through the 40 amp breaker, it could take up to a minute before the circuit breaker will trip. This is fine for almost all circuits found in automotive and Marine vehicles. This behavior of a circuit breaker can also help to diagnose whether the problem is indeed a short circuit, or if the problem is from too much current draw.