1Kit Contents: The self centering punch dowel jig kit has 1 locator jig and 7 spare drill bushings, 1 of bushings is already installed on the locator jig. 2Easy to Use: Adjust the position of the self centering doweling jig feet to fit different thicknesses of boards, and punch holes quickly and easily on the sides of boards with good perpendicularity and higher punching accuracy. 38 Sizes of Drill Bushings: There are 8 types of different sizes of drill bushings in the punching jig kit, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, in order to easily drill different sizes of holes to meet various drilling needs. 4Aluminum Alloy: The self centering doweling jig is made of aluminum alloy with good oxidation treatment on the surface, featuring high hardness, wear resistance, rust resistance, sturdiness, durability and excellent usage performance. 5Accurate Positioning: The self centering doweling jig is widely used for accurate positioning when punching holes in the sides of wood panels. The quick positioning of the openings allows for seamless splicing between panels.