To restrict generation of sparks in a process for removing a cover.

A service plug has: a lever 30; a cover 20 supporting the lever 30 so that the lever 30 can move between one side and the other side; a housing 90 provided to be fitted with and removed from the cover 20 with the moving operation of the lever 30, and in which the cover 20 is removed by moving the lever 30 from an actual locking position to a temporary locking position; a strong electric terminal 50 opening the power supply circuit by becoming in a non-connection state with the power supply circuit in a process for removing the cover 20; a detection terminal 60 switching from an ON state to an OFF state in the process for removing the cover 20; and a stopper 40 stopping the movement of the lever 30 from the actual locking position toward the temporary locking position by abutting on a restriction wall 25 provided to the cover 20 after the detection terminal 60 is switched from the ON state to the OFF state in the process for removing the cover 20 and before the strong electric terminal 50 becomes in the non-connection state with the power supply circuit.