This dowel jig is a great tool for woodworking projects. The splints on both sides are made of aircraft grade aluminum alloy with anodized surface, and the clamp body is crafted from heat - treated 45 steel, ensuring high strength and deformation resistance. It features high - precision locating, with holes precisely perpendicular and centered in the block. The clamps hold securely and evenly. There are engraved lines with large viewing windows for easy center alignment, making installation and drilling simple and accurate. The clamping range is from 0.4'' to 2.1'', allowing it to be used on boards of various thicknesses. It has a strong grip and can accurately align dowels on boards, suitable for making furniture like shelves, cabinets, tables, and chairs, as well as mounting railings. It comes with 6 steel bushings, enabling you to drill holes of the same size without moving the jig, and 3 premium twist drill bits made of quenching high - speed steel, which are tough, hard, rust - resistant, and not easily broken. This self - centering dowel jig can create multiple types of joints, keeping boards aligned and flush. Size: medium.