#1 Morse Taper Mandel Pen Mandrel is one of the most popular Pen Mandrels which will allow you to adjust to different lengths, easily and accurately achieving the perfect mandrel length for any project.  The 7mm, adjustable mandrel slides through the collet and is tightened with two wrenches to hold in place (note: these are not included). You can then mount your tubes and bushings, adjust it to the length you require and finally lock it into place. Also included with the mandrel are 5 x slimline bushes which can also be used as spacers if required.