This AC WORKS brand inlet wiring device is a heavy-duty power input connection device. It is used for an industrial and commercial grade flange inlet. This inlet works with 10 AWG(American wire Gauge) copper wire and is commonly used for residential, transfer switch, cabins and generators. Residential, Generator, Transfer Switch and cabin power inlet 30 Amp, 125/250 Volt Inlet NEMA L14-30P Power Inlet UL and C-UL certified 1-year limited warranty