Product Description Bosch 85244M 1/4" Carbide Tipped Pilot Panel Bits with Drill Through Points. Bosch router bits are distinguished by a careful selection of materials, exactly calculated cutting geometry, long bit life, extra sharp cutting edges (ground with diamond honed grinding wheels) and low vibration operation as a result of a special casting process during manufacturing. The working lengths of all Bosch router bits have been matched to the normal thickness of standard solid wood and wood materials. Longer shanks are held more securely in the collet and allow utilization of the full working length of each bit. Bosch's patented micrograin carbide is designed to keep a sharp cutting edge up to 30 percent longer than standard micrograins in difficult woodworking applications, resulting in less frequent bit changes, added productivity and reduced costs. Router bits with tungsten carbide cutting edges or solid carbide bits are especially suitable for use with tough abrasive materials and last several times longer than HSS bits. Use for different groove and profile cuts in solid wood, glued boards and hard plastics All bits must be inserted in the full length of the collet. Be sure to use only router bits and accessories specifically designed for your router Carbide tipped pilot panel bits are micrograin bits for window and door cutouts in abrasive insulation materials, plywood and paneling. Features a drill-through pilot for guiding on a templet or framing after the panel has been mounted 85244, 85245 and 85246 are not micrograin bits