Contains the sizes of 7 mm (0.28 inch), 8 mm (0.32 inch), 9.5 mm (3/8 inch), 10 mm (0.39 inch) in diameter, 3/4inch steel cutting head, hex key wrench and "O" style sleeve adapter, which is acceptable for most kits, can be applied for most lathes. This pen trimming set is made of Metal of the cutter shafts, rust-proof, , has good cutting strength, long service life, to meet all your needs. The sleeve adapter of the pen trimming system is made of brass, and the spindle of the lathe is made of high-quality steel, which is tough, wear resistant and high temperature resistant, helping to reduce vibration encountered during rotation. Our carbon steel shaft are incredibly versatile, suitable for mounting on lathe chuck, drill chuck, drill presses or hand drill and help to grind holes, polish pens and clean fine inner tubes, making them a must-have for any pen enthusiast. Our mill trimmer set for woodworking are designed for easy maintenance, which can easily clean off the wood chips, excess