The Joywayus Self Centering Dowelling Jig is a woodworking tool that allows for quick and easy dowel joinery. It is made in China with good quality materials Positioning dowel: 1/4 inches,5/16 inches,3/8 inches. Adjustable to clamp on different thickness of wood boards from 17mm to 50mm, quick operation, simple and convenient. High-quality and Durable Material--The joinery punch locator is aluminum alloy 6061 steel HRC50(drill bushing) brass (nut),ensures good work performance and helps to improve efficiency. Imperial Dowel Jig Tool Self Centering Dowelling Jig, Drilling Guide Bushings Set 60mm Width Accurate Positioning For Woodworking Adjustable Woodworking Jig Buy 3 In 1 6/8/10/15 Woodworking, Doweling Jig Dowelax Jig Self... High quality aluminum alloy 6061(drill guide) and die steel(bushing), high hardness and strength, good wear-resistant and durable to use. Convenient and Practical--With the practical joinery punch locator, you can more conveniently work for woodworking. Rdeghly Dowel Drilling Guide, Woodworking Drilling Guide,6/8/10mm Self It is a great tool set for both furniture factory and woodworking enthusiasts.