Why oh why did I read the instruction manual? The box says 20 amps required and has a pic of the installed 50 amp plug. Got the breaker, receptacle box, receptacle, cable, plate, and made an extension cord with flexible 3/10 wire. Then for some unknown reason I read the instructions, never bothered much with those in the past. The manual says to use #12 wire and a 40 amp super lag breaker. Not only am I not a welder but I'm not an electrician either, but seems to me if I put in a 40 amp breaker with a slow blow and it's needed for some reason, it's going to heat up that 12 gauge wire and burn my house down. We can't have that, my wife is inside making me another cup of coffee and my car and bike are both in the attached garage with my 10 year span of sports illustrated swimsuit calendars. I don't even know what a super lag breaker is. But like I said I'm not an electrician.