[High Precision]Self-centering pin fixtures are machined by precision CNC machine tools. When the middle bolt is turned, the aluminum on both sides are tightened at the same time, and the board is clamped evenly so that the perforation position is in the exact center. Front-view drill aid marking lines for direct center alignment, making it easier to use. [Self-centering]Self-centering woodworking dowel jig, more suitable for making different wood dowel joints, realizing simple and convenient precision drilling, more accurate positioning, leaving no offset or Space. [Excellent Quality]The surface of the fixture is anodized, with bright colors, scratch resistance, acid and resistance, and will not fade after long-term use. The central iron piece is treated with alkaline oxidation, and the screw rod is chrome-plated to prevent rusting and is stable and durable. [Application and Use]It is very suitable for some woodworking DIY projects to do the splicing work of wooden boards. Self-centering pin fixtures: 20mm size: about 192 x 39mm Material: metal colour: Black Package Contents: 1 x Woodworking table hole dowel Kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.