The Bosch 2608595491 is a SelfCut Speed Flat Drill Bit Hex Shank 20x152mm. The Self-Cut Speed Spade Bit performs extremely fast hole drilling. Its self-feeding threaded tip enables the drill bit to effortlessly pull itself into the wood for high-speed drilling with little exertion. Fast chip removal for rapid results is made possible by the specially shaped spade. In product tests, this drill bit produces holes 10 times faster than a standard spade bit. It is suitable for use on soft and hard wood, light building materials and plasterboard. This spade bit has a 1/4-inch hex shank system and it is best for use with portable power drills.