Suitable size: the pilot shafts include diameters of 7 mm (0.28 inch), 8 mm (0.32 inch), 9.5 mm (3/8 inch), and 10 mm (0.39 inch); the cutting head measures approximately 19 mm (3/4 inch) in external diameter and 6 mm (0.24 inch) in inner diameter; the "O" style sleeve adapter fits pilot shafts over 7 mm to maintain center position Quality material: the cutter shafts are constructed from solid carbon steel, offering rust resistance, strength, and durability with excellent cutting performance for efficient drilling; the sleeve adapter is made of brass; this pen barrel trimmer kit provides a practical and convenient solution for pen blank preparation Easy to clean: the cutting shafts allow for easy removal of excess glue, wood debris, and impurities from tubes, helping achieve a flatter tube cut; ensure the cutting shafts are properly secured in a drill or lathe chuck before use Various applications: the pilot shafts are compatible with drill chucks, lathe chucks, drill presses, and hand drills; they are useful for pen polishing, hole milling, and cleaning inner tubes due to their compact size Increased efficiency: the set of pilot shafts in multiple sizes meets various needs in woodworking and daily use, improving work efficiency and reducing effort during drilling and milling operations Durable cutting head: the cutting head is solid and long-lasting with a pointed cutting edge; it is designed for repeated use without quick dulling and can be easily sharpened to maintain a flat cutting surface Color: Silver Material: Metal Package Contents: 4 x pilot cutter shafts in different sizes 1 x cutting head 1 x sleeve adapter 1 x hex key wrench Note: Contains small parts; keep away from children Only the items listed are included; additional products not included Note: Lighting and display differences may cause variations in the item's color appearance