Feature: 1. Wear Resistant And Durable: Self centering doweling jig is made of good quality material, wear resistant, durable, and corrosio resistant 2. 6mm, 8mm, 10mm Hollow Nuts: There are a variety of 6mm, 8mm, 10mm hollow nuts, easy to replace, to meet the various needs of users 3. Adapt To Center of Board: Doweling jig can adapt to the center of the board, install the dowel after punching to join the two boards 4. Positioning And Drilling: There is an angle of 90 degree, which can be used for positioning and drilling the wooden stick and the 90 degree wooden block 5. Oxidation And Electroplating Surface Treatment: Using oxidation and electroplating surface treatment, not easy to damage, bring longer service life Specification: Item Type: Self Centering Doweling Jig Material: Aluminum alloy + carbon steel Surface Treatment: Oxidation + electroplating Hollow Nut Hole Diameter(3pcs/each): Approx. 6mm / 0.24in, 8mm / 0.31in, 10mm / 0.39in Positioner Size: Length: Approx. 10cm / 3.9in Maximum Width: Approx. 9cm / 3.5in Height: Approx. 4cm / 1.6in. Package List: 1 x Positioner9 x Hollow Nut1 x Wrench Note: Keep away from children, take good safety protection when using.