For LEE single stage press. When doing a large run of sizing/depriming or flaring this helps. My left arm doesn't get as tired! I glued a brass strip on the priming thingie using JB Weld then bent the strip to make it work. It kicks the case out into a bucket. I put it on the large primer thing cause I only use small pistol primers. This was invented by a friend of mine and I did some slight modifications.