Very interesting attachments, which allow you to cut neat and uniform chops out of wood with a drill. The chops are cylindrical. To get the result it is necessary to drill into the board thickness coinciding with the size of the nozzle, as sawing off the cylinder from the base of these nozzles can not. Excellent thing for making plugs under the fallen knots in the wood when making furniture. In the comments, they also share a trick for disassembling pallets: with these nozzles you can easily drill out the wood around nails.