NEMA L7-20 Grounding Locking Receptacle
The receptacle is designed for #14 through #10 AWG.
Make sure the receptacle has the proper electrical rating for the system on which it is being installed. Wire size and type must comply with appropriate local electrical codes. Use copper wire only. Make sure the wire is clean and a bright copper color. AC Only. 60 Hz. UL (US Listing).