Review on Timberline 20200 Countersink: Adjustable Diameter for Precise and Versatile Drilling by Chris Bowden

Used for a year. This is a much better investment than HSS bits, which will survive one reaming cycle and then end up in landfill. The carbide stays sharp and effortlessly cuts through Australian hardwoods leaving a clean hole. A clutch with two hex keys holds the bit in place, as opposed to a clutch with a single set screw that pushes into the bit's shank. Love the fact you can use this for 6 inch bits when drilling deep holes. The only downside is that you have to switch drill bits for different diameter holes, but this can be solved by buying more than one. Arrived as an Amana tool, made in China, well designed, I wouldn't go back to standard countersink bits after that.