If you Swarovski Crystalline pen uses an adapter and makes the refill over 4" long, These Will Not Work You must make sure your refill and adapter are under 3" if using these for a Swarovski Pen Each Set Comes With 1 Re-usable plastic Threaded Cap. Some Pens Do Not Need This, Please See The Pictures As Some Pens Us An Adapter 30 Day Satisfaction Guarantee, No Hassle Returns If Not Satisfied Measures 2 5/8 inches Long (66mm), Available in Black, Blue, Red, Green, Purple These refills are Compatible With Swarovski Crystalline Pens, Cross 8518-4, Lamy M21 and most Multi-Function pens. Please compare the size to your current refill. Brand names mentioned are registered trademarks of their respected companies and names are only used for compatibility reasons