So I took the advice and decided to make my own extension cord instead of buy one. I got the cable and male plug from HD with out any problems. But I cant find the female plug anywhere locally. So I found one from McMaster Carr but its $50 which is pretty rediculous. All the places around here (HD and Grainger) said I should just put a box and a plug on the end but I dont think thats the right thing to do. Is it even safe? So should I just box it? Which box is better metal or plastic? Or a cheaper place to look for the plug?