This 120V Rocker type switch has 2 terminals and a compact design for easy installation. This genuine Porter Cable replacement part is sold individually. Switches are commonly replaced parts in power tools. A switch handles on/off and variable speed functions. They also have a role in electric breaking; they can momentarily reverse elec...Read moretrical polarity. Because switches use mechanical internals, they will degrade and wear out over time, eventually requiring replacement. Some common signs of a broken or failing switch are:rn • The tool has completely stopped functioning - it will not turn on.rn • The tool operates intermittently, requiring multiple tries to turn on, until eventually it won't turn on at all. • The variable speed function and electric braking aren't working properly.