Please refer to the instructions in A+ for details. Self-Centering Dowel Jig This doweling jig automatically centres itself on any board from 10mm to 60mm wide. The jig comes with two sets of... Drill-hole Sizes: 1/4, 5/16, 3/8, 7/16, 1/2. Woodworking Drill Jig Self-Centering Doweling Jig Kit - 6 Size Aluminum Drill Guide For Woodworking Biscuit Joiner Set Steel Bushing Dowel Tool Quick Self Centering Doweling Jig Vertical Positioning Hole - Belgium Dowel Hole Alignment Tool Warm Tip: If the left and right distance of the splint is found to be asymmetric during use, it can be easily adjusted by yourself. Self Centering Dowel Jig - Online Best Price 2022 Drill equally space hole along the wood. 6 hardened steel bushings: 2 each of 1/4, 5/16, 3/8.