The Cross M 8513 black ballpoint pen refill offers the original performance and worldwide reliability recognized in Cross writing instruments. Equipped with an exclusive oil-based ink formula and a medium (M) tip, this refill ensures a smooth, clump-free flow, guaranteeing extremely smooth writing on any type of paper. Its brass construction and durable materials protect the ink from premature drying. The classic and versatile black tone makes this refill indispensable for those who use the pen in a business context, ideal for daily document management, formal meetings, and office tasks that require an impeccable presentation.