Review on Leviton 2321 Locking Industrial Grounding by Daniel Steele

About the same price at a big store other than the time and gas to go there. It is very easy to install. On the inside are markings showing earth, hot and neutral. The ground screw is colored green to provide additional assurance that the correct contact is used. In my case since I was connecting 1 phase 220v I just had to make sure the ground was on the correct terminal and 2 phase 220v can be swapped. The stripped wires were simply inserted and securely clamped with individual contact screws. The strain relief cover and then the strain relief were slid over the open connector and screwed in place. The strain relief does a great job of preventing the wire from being pulled out. I made the mistake of originally purchasing the 30 amp version of this plug and found that the pins are larger than the 20 amp version and it will not fit a 20 amp outlet.