Legacy Woodturning, Fancy Pen Kit, Many Finishes, Single Kit Finish: Copper Type: Ballpoint Twist Pen Mechanism Drill Sizes used: 7mm; Compatible Tube Sizes: 7mm Bushings: Slimline; Blank Size: Minimum  x 2-1/32; Refill Type: Cross Style Skill Level: Easy; Bushings, Blanks, and Refills sold separately