This is a immature 30, 125/250V, 3 Pole, 4 Wire, Grounding Locking Plug of nylon construction. for connecting to a generator with a 120/240 volt outlet or cord end. I have alike plugs with 12-4 and 14-4 600 volt rated wire and 10-4, 12-4 and 14-4 300 volt rated wire. UL but does not work on 8 gauge wire or 10 gauge with 600 volt insulation or higher rated insulation. : L14-30P Plug 2P + N+G Product Specification : 30A 125V/250V ~ Rating : 125V/250V ~ Electric Current : 30A Color : black/white Dielectric Strength : OVER 100M MIN at 500V DC Insulation Resistance : AC 2000V 1 Minute Body Material : PA6, H62, PC Grade : 94V-0 Approved : UL E314240 .