The plastic handled tech that I have doesn't have metal threads or anything, all plastic. It was in a box with some other stuff and the threads from the previous head had broken off in it. Surprising that the plastic was stronger than the metal, although I think it was aluminum. Got it out and put the travel Tech head on it. Kids have fun playing with it.Strange looking handle. I wonder if it has any metal fittings at all? Is there a metal nut pressed into it?