Pen Barrel Cutter System: Includes 4 pieces of different sized pilot cutters, 1 cutter head, 1 sleeve adapter and 1 hex wrench, suitable for inserting into a drill chuck, lathe chuck, drill press or hand drilling, and are useful for polishing, hole and cleaning the inner tube with the small size Pen Turning Chuck: The lathe chuck is designed for producing pens, including a useful pen chuck saver for woodworking. Easy to install, clamping the tailstock locks the chuck, which can reduce off-center rotation, the shaft length can be adjusted at will by loosening the lock nut at the end of the headstock, which can also help you improve work efficiency Proper Size: Pilots contain the sizes of 0.28 inch, 0.32 inch, 0.37 inch, 0.39 inch diameter; The cutter head measures about 0.75 inch outer diameter and 0.24 inch inner diameter, and the "O" style sleeve adapter fits the pilot shaft more than 7 mm to maintain center position; The woodworking pen chuck measures 7.95 inch total length and 0.24