These are great fletching tools, IMO. There is a little screw at each end of the clamp that allows you to fine tune where the fletch winds up on the shaft. Needs to be tweaked to goto different diameter arrows. And the best way to afix the clamp to the magnet, when it is holding a fletch with glue, is to get the rear of the clamp down first, against the nock turret, and then swing the front end down against the shaft. Once you get it adjusted, the darn thing is nearly foolproof.