Silver Series Primary Manipulation 1Primary Manipulation 1 Experience the beauty and quality of Primary Manipulation 1, a handcrafted pen from Silverburlpens. Made with material from the Carolina pen co, this pen features a polished steel Jowo nib size 6 and comes with a Schmidt K5 ink converter. Custom nib sizes are also available upon request. The pen measures approximately 145m m long including the cap, with a body length of 135m m and a diameter of 15m m. The cap has a diameter of