Experienced pen turners understand the disadvantages of the traditional pen mandrel, overtime the mandrel can slowly work its way out of round and introduce a wobble into your turning. You can replace the mandrel with a new one, but now you can get it right the first time! This set includes a 7mm drill bit, 3 bushings, the Mandrel Saver Tailstock Centre PLUS a basic mandrel (no threads or knurled nut) that works great with your Mandrel Saver. Here's a complete mandrel system for just a bit more than the cost of a new mandrel.