Amzdeal 2 Poles 2 Wires 15 Amp 120V Earth Leakage Protector Switch GFCI Plug Outlet Tester Compatible with 15 amp U-ground 2- or 3-wire outlets and plugs Plug fits any power tool or machinery cord to reduce the risk of shock Power Indicator lamp goes OFF if GFCI trips, power is interrupted or the GFCI is unplugged Fully complies with NEC and OSHA regulations for construction sites Open-Neutral protection immediately trips the GFCI if the neutral conductor on the line side is opened, eliminating the possibility of the GFCI having a live hot leg