Schmidt 635 Mini D1 Ball Pen Refill with Plastic Refill Holder- Blue Ink, Medium Tip - 8 Pack (Lamy M21, Cross 8518-4 and Swarovski Pen Compatible) - Walmart.com
Swarovski Ballpoint Pen Refill Black #1079448 (Box of 20 refills)
How to change pen refill for Swarovski pen (old and new version) I justGrace - YouTube