ETL Listed High quality standards. 10 gauge 4 prong SJTW 125250V up to 7500W, NEMA L1430P male to L1430R female twist lock, ETL Listed Emergency Ready This generator extension cord with inlet box provides a safe and convenient way to connect your generator to the manual transfer switch on your house, providing the power you need in bad weathers. Also for house building Pre Drilled The 4 knockouts were replaced by rubber plugs which are easy to remove directly without damaging the power inlet box. Never need a special tool such as drillerknockout punch to drill. Easy to Open Heavy Duty Pure copper wiring coated with a heavy duty flame retardant, heat resistant, UV resistant PVC, provides protection from rain, wind, snow, soil, and rocks for emergency ready Easy to Organize Comes with a lovely storage bag and adjustable cord organizer that makes carrying and storing simple after use