The Sheaffer T black M 99337 ballpoint pen refill offers the smoothness of a medium (M) tip combined with the intensity of a deep black tone. Made in a metal tube with a high-precision tungsten ball, it guarantees hundreds of meters of consistent, flawless writing. The vibrant black color ensures high contrast and formal readability on documents. It is the most recommended standard refill for Sheaffer ballpoint pens.