PKM-FSM is the quickest and most convenient pen mandrel on the market. The "keyless" feature allows you to instantly hand loosen and tighten the collet that secures the 7mm mandrel shaft (.244" OD). Plus, you can quickly slide and lock the shaft so you get the exact length of your turning and a perfectly concentric fit. You’ll no longer deal with the hassle of spacer bushings or separate tightening wrenches. The system also includes (5) 7mm bushings, (1) knurled nut, (1) 7mm Brad Point drill bit, and (2) tightening bars to use if needed. Replacement shafts (XPKM-ELC) are available from Penn State Industries. PSI Woodworking Mandrel Savers (PKMSTS1 & PKMSTS2) are compatible with this shaft. PSI Woodworking has many other mandrels available to meet your specific turning needs: PKMS2SET, PKMS1SET, PKM-ELC, PKM-FLC, PKMSMAN1, PKMSMAN2, PKM-AL, PKM-BL, PKM-CL, PKMBCM1, PKMBCM2, PKMBCM3.