Cross 8521 Refills for Selectip Gel Roller Ball Pen, Medium, Blue Ink - Newegg.com
Cross® CRO-8521 - McKesson Medical-Surgical
Amazon.com: Cross Gel Ink Rolling Ball Refill for Selectip Pens, Pack of 1 : Office Products
Jaymo – 2 Blue – Replacement for Cross Selectip 8521 Rolling Ball Gel Pen Refill – Smooth Writing Ink and Medium .7mm Tip – 4.375 in / 111 mm Long – Measure Yours Before Ordering – BigaMart
Cross Selectip Gel Rollerball Refill (2 Pack) - Blue, Medium - Anderson Pens, Inc.