Sorry for the pun in the title. The product itself is worthy - in this case, it is hampered by the lack of any documentation. The pieces of sandpaper slide nicely over the rollers, but what they don't mention is that you need to adjust the thickness of the rollers to keep the paper strong. I used a large drum to round the outside edges on a recent project, but the sandpaper wears out pretty quickly. They're cheap so it's not really a problem - they did their job. I recently bought a $50 Ryobi CL grinder and now they're basically taking up the drawer. A great solution in a pinch if all you have is a drill press. highlighted.