It was basically a piece of wood with two different sized rubber bumpers on both ends. You would tap it with a hammer to knock out stuck slides.
I have been trying to track one of these down. I have mentioned it to our road guys and they seem to think I'm making it up. I loved it. It always worked for me and I hate the hook or strap that they want to sell me now.
If anyone can tell me what it was called or if they still exist, I would be so grateful.