Just went to flex flex web site and there are in fact the old pro nocks that many of us competition shooter shot back in the 80's. I had no idea they were still making them. I have a stash of them here some where, and I thought they were the best nock out there at the time. The only problem we had with them back then, was the lips on the end of the nock were very very sharp. And while pulling an arrow from the bales, if your leg was in the way, it would give you a nice cut. Had to be careful with them