Mitsubishi Pencil ballpoint pen core replacement jet stream prime multicolor multi-function for 3 pieces 0.7mm black red blue 164 178 002

Seem like the genuine article.

Very good

Exactly what I was looking for. Ink runs smooth

Fits well as aftermarket refills.

These refills write super-smoothly... put down what seems to be a good amount of ink. No idea as to the longevity - but then it IS a small format ink tube. I fully expect to reorder these as needed in the future.

These cartridges fit my Rotring 4 in 1 combo pen/pencil very well. It now works like it did when I first bought it!

The ink writes smoothly and with ease. I really like the circular indicator color near the tip, because when I select an ink from a multi-ink pen and/or if I leave the ink extended and pock up the pen later, I know exactly which color I'm going to use. Other brands don't have this, which means I have to scribble on something to confirm which color I'll be writing with.

They work well in my Yasutomo quad point.