F-Series Ballpoint Stainless Steel Refill, Fine Point, 0.8mm, Black Ink, 2-Count

If you want an adult pen then here it is. I am a machinist (I work in industry) and this is the single best investment. The size is perfect, they are durable, the line size is small enough for the little boxes I have to fill out but it rolls smooth enough it doesn't rip paper. It doesn't bleed and you can buy ink refills.

I love this slim power tank refill. I use these in other pens that come with poor quality refills. I have a few packs of the full sized power tanks, but the refills are very thick. These are the only pens that work constantly in the welding shop.

A very good pen refill. Smooth flow. Fast-drying ink.

I love this pen. Been using it for about a year now. Sturdy, we'll made, and a joy to write write with!

Good 👍