Wondering if you guys can help me out because I can’t find anything about this item number online. I was just gifted an old but in really good shape Craftsman 919.178110 compressor. It a 1HP 12 gallon and will do what I need it to do which is to blow out my sprinklers. Would any of you guys with a 919 know what size the drain plug socket is? I don’t have any and will need to buy one for it. Going to add a regulator as well as it doesn’t have one. Thanks