Unless you have an accurate mandrel, you may as well give up on making pens. I made the mistake of buying a no-name brand of mandrel and it was inaccurate. After blaming my first few disappointing results on my own ineptitude, I tried this Dayacom Brand pen mandrel at the WCWA club in Pinelands. That was the first perfect pen i turned. Although the club mandrel is a MT2 taper it is the same high quality mandrel as this. All my fellow clubmates praised my efforts and the next day I bought myself my own Dayacom mandrel. One can easily extend or shorten it depending on which pen you are making. I actually bought 2 bushing sets and I now make 2 Sierra pens back-to-back at once on the same mandrel. I highly recommend this mandrel for being accurate and easy to use.