I want to try before I buy, next time, but I don't think they let you do that I now have a friend who has some of just about every sort, though, maybe he will let me experiment sometime. Clover clamps, they get tighter when pulled, and I've seen a magnetic kind. Neither looks particularly nice, but I don't know, like I said, I haven't tried them.

I'm thinking a written test will be more my style than a practical, is that ok?