Thanks Stan! Something very important information! Might put it in the Ryobi folder. It's the only thing that ever went wrong with Mine!I had the same problem with my Bosch POF 500A. Replaced the missing brass piece with a small ball bearing inside the locking handle slot. I was cautioned to tighten gently as it can damage the plunging rods if too tight. Fortunately I found the missing piece the next day on my garage floor.