Disclosed is an apparatus for selectively permitting electricity to flow to a power tool having a power cord. The apparatus comprises a body having an exterior surface and having a passage therethrough. The passage contains an electrical relay having an electrical input side and an electrical output side. A switch on the exterior surface of the body selectively closes the electrical relay upon activation by a user. A mounting portion on the body is adapted for securing the body to the power tool and a power receiving portion in the body receives the power cord of the power tool. The mounting portion has transfer wires associated therewith in electrical connection between the output side of the relay and a power switch of the power tool. The power cord is in electrical connection with the electrical input side of the relay.