Silver series SpectrumIn house cast blank used to make this pen, It features a polished steel Bock nib size 6 and comes with a Schmidt K5 ink converter. Other nib sizes are available upon request. The pen measures approximately 145m m long including the cap, 135m m from nib to body end, and has a body diameter of 14m m with a 13m m thread. The cap diameter is 15m m. The silver used in this pen is Argentium . 940, which is whiter and brighter than traditional . 925 sterling