Fast and easy to use. High hardness, strong torque, quality assurance, durable and long service life. Material: aluminum alloy 6061+steel(drill bushing)+brass (nut), Material of drill bushing: Steel HRC50° Anodic oxidation treatment surface & Steel HRC50° material ensures good work performance and helps to improve efficiency. Adjustable stop and drill accurately, drill equally space hole along the wood. Suitable wood size: 17-50mm. Product description It is a good tool set for both furniture factory and woodworking enthusiasts. Adjustable to clamp on different thickness of wood boards from 17mm to 50mm. Specifications: Material: Aluminum alloy6061(drill guide), die steel(bushing) Material of drill bushing: Steel HRC50° Material: aluminum alloy 6061+steel(drill bushing)+brass (nut) Surface treatment: Anodic oxidation treatment Anodic oxidation treatment surface & Steel HRC50° material ensures good work performance and helps to improve efficiency Suitable wood size: 17-50mm Positioning