Bosch Hdgqa 3/8 In. Autostart Carbide Hole Saw Quick Change Mandrel, Black Product Description Now you can work faster and smarter - using our Quick Change universal hole saw system. Its advanced design allows you to change any size or type of hole saw in seconds and offers easy plug removal. Fits all major brands. From the Manufacturer Bosch Power Tools and Accessories is one of the divisions within the Robert Bosch Tool Corporation, which is one of the largest power tool and accessory manufacturers in the world. Bosch provides a complete line of corded and cordless power tools and accessories engineered to survive any jobsite and allow professionals to take control of their work. AutoStart pilot bit is spring-loaded Retractable shaft allows walk-free cutting without a pilot hole Carbide tip provides extended life in porcelain and granite Pilot bit offers unique grind that starts holes accurately every time