Uni-ball 4 Color Refills for Uni Jetstream Multi Function Pen, 4 Color Ballpoint Pen(MSXE510007), Fine Point 0.7mm, 4 Color Refills, SXR-80-07, 12 Total Value Set

In this particular series :) Excellent. Uni Jetstream 3&1(Three colors 0.7 plus mechanical pencil) Multi unit. And the uni jetstream 4, Red, green, blue and black, And uni Jetstream3 Blue, black, red. no smudging I have the capability to perform free-hand, graphic ink pen art(INK+PEN=ART:) The ink drives relatively quickly, very crisp, clean cut lines, No oozing or bleed out or bulging of ink, And since” I’m left-handed”, the ink drys so quick I don’t have to worry about the smudging.(THIS IS AN EXCELLENT INK PEN FOR FREEHAND GRAPHIC Illustrators and technical detailed artwork; for ARTIST, USING THE PEN & INK-medium. additionally For the price$$$It’s not a bad deal. It’s very excellent these pens and refills with the mechanical pencil.(AND THE DIAMETER OF THE FINGER GRIP PART COMBINE WITH THE HIGH ATTACHED POCKET CLIP:) in my opinion is high-quality.(And I pretty much been doing INK-PEN ART for over 40 years)

I enjoy using my jetstream pen and these extra inks do a great job making sure my pen is still usable.

I bought these to replace the crappy, dull, skipping ink in a Pilot Dr. Grip 4+1 pen, based on a YouTube review of that pen that claimed these refills fit it. They're too short by about a half-inch. I was able to customize the pen by carefully removing some length from both the top and bottom sections with a small rotary tubing cutter, and now it works great with these refills in it. The ink in these refills writes much more smoothly than the ink that Pilot puts in the Dr. Grip. This ink flows smooth as silk, doesn't skip, glob, or smear, and dries instantly on the paper. The colors are very vivid, probably the most vivid inks I've used. Overall happy with the purchase, and seeing how well these inks write, I was inspired to order a Uni Jetstream 4+1 pen, which is the pen these are made for.

They write very smooth and inflow is good

As advertised, works as well as the originals I had did.

No smears. Writes smooth as butter!

Why did you pick this product vs others?: Lives these pens, they work perfect in my JetStream pens.

I use these for work and have for 6 years. The pens and the refills are worth the money.