Uni-BallSigno Gel Ballpoint Pen Refills For UM151, Blue Ink, Extra Fine Point 0.38 mm, 6 Pack (Japan Import)

It saves otherwise the pen of no ink.The refill is as smooth as original.

These refills do not fit in my pen. They're different than the American market's refills.

for lovers of fine points, I highly recommend these .38 refills. And you get to reuse the pen instead of adding more plastic to the universe.

Came after the day I bought it and I’m really satisfied with this product.

0.38 blue, rarely breaks before ink is used up

Hard to find but it’s worth it. Thank you