The Rotur Pen Mandrel Shaft and Nuts Set is an essential accessory for pen turning enthusiasts. Made in the UK, this set includes a high-quality steel mandrel shaft with a diameter of 6.17mm and a 1/4" BSF thread on one end. The Brass nut and locking nut work make for very secure and precise clamping of the pen blank. The shaft is precision ground for maximum stability and accuracy during the turning process, and the nuts feature a durable and easy-to-use design.  This set is compatible with the Rotur Original and Deluxe Mandrels as well as most standard pen mandrel accessories. It is essential in any pen turning kit. Shaft and Nuts: PM4S