Barrel Trimming Sleeve Sets (PSI)Pen Blank Barrel Trimming Sleeve Set 5 Piece or 9 Piece Set Perfectly trim your pen blank barrels with these barrel trimming sets. Slide the sleeve on the shaft of the trimmer or jig and slide the shaft into the tube. You will get an exact 90 degree squared blank every time. The 5 sleeve sizes will insert into tube sizes: 8mm, 11 32 in., 3 8 in., 10mm, 25 64 in., 10. 5mm, 15 32 in., 31 64 in., and 12. 5mm. The 9 sleeve size set will insert into tube