【Precise Positioning】There are 5 different sizes of standard drill holes, namely 1/4", 3/8", 5/16", 7/16" and 1/2", with three different sizes of sockets, 2x 1/4", 2x 5/16" and 2x 3/8" to create different types of dowel joints, thus achieving simple and precise drilling. 【High-quality Material】 Our fasteners are made of industrial aluminum alloy, which is durable and rust-resistant. The guide hole of the self-centering doweling device is threaded to locate the drill bushing stably and drill precise holes. 【Stable Clamping Pressure】The steel block and thumbscrew handle securely clamp the tools like a vice, and the jig with sturdy aluminum sides holds the work securely without easily damaging the wood. 【Easy to Install and Use】Our Wood Drill Guide is easy to adjust and can be clamped on boards of different thicknesses. The bushings of different sizes to achieve simple and convenient drilling, suitable for drilling and joints of wooden boards, it is an ideal tool for panel furniture.