Pilot Hi-Tec-C Slims Gel Ink Multi Pen Refill - D1 - 0.4 mm - Blue

Perfect. Not too scratchy but not too smooth which causes bad handwriting.

I have 3 Zebra Sharbo X LT3 (green, orange and, gray ). They fit perfectly. This pen is just magnificent.

Excellent refill. Thin line, not too smooth that could make your writing bad and not too scratchy which makes you slow and inconsistent like the 0.3.

Just horrible. I LOVE super fine tip pens but this refill does not work. I got 8 of these and so far 4 dont work and when they do its a faded double point gray line.

I judge my multipens by whether or not they can fit this component. This is the best writing instrument. It isn't as smooth as a wider tip; however, the very slight scratchiness gives you greater control over each of your characters. The line is extremely fine and looks perfect.

A nice quality refill. Tried it to get the Hi-Tec-C experience in a Sharbo X multipen. Unfortunately, it's too loose and won't fit snug. The refill will fall out of the pen if your try to use it. A remedy was to put a small piece (2mm long) )of scotch tape on the top of the refill, and it will fit with friction. The ink is not as good as the Sharbo X refills (not as water-resistant), but will be smoother to left-handed writers.