Router collet extension for 1/2'' shank bits, need to tighten with wrench to prevent bit from falling out. Made of heavy-duty steel for long life, convenient to use. Eliminate the dangerous temptation to pull the shank off the collet, extend the bit to provide the full depth of cut. Make you more efficient in processing products, suitable for wood cutting, milling, engraving. Package content: 1 x 1/2'' shank collar extension Product description Feature of Clamp Extension: This clamp extension is made of industrial grade material, high precision, strong and sturdy for long service life. < p>This router collet chuck provides the extra cutting depth needed for many routing tasks. Easy to use, better to control, it will improve your work efficiency. Use it to achieve full depth of cut when machining dovetail flutes, ideal for your woodworking. Collet Extension Specifications: < p>Material: Hard Alloy Black Color Shank Diameter: 1/2 inch / 12.7mm Holder Diameter: 1/ 2 inch / 12.7 mm Total