Top Writing Quality Black ink refill has smooth writing, waterproof, fast drying performance. The ink dries quickly to prevent smudges, making the paper look elegant and tidy. Gives you a Unbeatable writing experience. Universal Compatibility The ballpoint pen refill is compatible with many ballpoint pens, help extend the life of your favorite expensive pen. Long life & Durable The life of the refill is quite long. Refill pen body made of metal stainless steel, and there is a lot of ink in the refill, the filling tip is sealed with a protective wax, which means that the extra refill you will not dry out while waiting for use. Multipurpose These refills are suitable for work, school, hotel, restaurant and various writing occasions; Nice refills for office supply, school stationery, family use. lightweight and portable, easy to carry. Specification: Ink Color: 5Black + 5Blue length: 3.9 inches Tip: 1.0mm Material: Stainless steel Package: 10 refills in a self-sealing exquisite box. Warm Tips: 1.The refill is initially for B5/B6/B8 ballpoint pens in our company. Search these for more details: B07JJ7C4L8, B07JH9FJGX or 07JFNN2GW. Also, you can just input""on search box. 2.The refill is applicable to generic tactical pen and ballpoint pens of other brand like Parker. But you must carefully check the specification of the refill to see if they can match your original pen properly. 3.You can remove the spring from the narrow part of the refill, just with a little bit force. When its service life comes to an end, the spring can be reserved as a backup gadget, if necessary. Sincere After Sales Service: If you have any question or advice about our products,please feel free to us. ★WIDER APPLICABILITY--- The refill is Parker Waterman Compatible Ballpoint Pen Refills and original cartridge of B5/B6/B8 ballpoint pens(Search 'ballpoint pen'on ). Also applicable to most other brand standard size ballpoint pens, twist action pen, include compatible with Parker ballpoint pen. This is a great replaceable refill, Easy to put in the pen for universal writing, suitable for all papers. ★DIMENSION--- The total length is 9.9 cm(3.9 inches). The diameter of the ink reservoir is 0.6 cm(0.23inch). The narrow part where the spring sits on is 2.6cm(1 inch). 1.0mm tip, pack of 10, 5 blue + 5 black. And we must remind you to double check the detail of the dimension. ★SUPER SMOOTH WRITING EXPERIENCE--- Releases ink in a smooth and consistent manner. Ink dries quickly, does not penetrate-- no smear, no smudges, without clumping. The body of the refill is made of stainless steel, feeling light and premium ★EXTRA BONUS--- Each refill comes with a spring which is already fixing on the stem.You don’t have to worry about missing spring or the refill don’t fit your pre-existing spring. ★PERFECT PACKAGE--- 10 refills of one pack. Refill tip is sealed with protective wax to keep the ink from drying out, easy to remove. This is a good choice when your expensive pen runs out of ink, you don't need to throw it away; the package comes with a 10-pack refill that is enough for you to use.