The Bionic Worker roller ball pens were designed by Stabilo for demanding professional use. The ink flows smoothly and produces a medium line great for every day writing needs. A small nub on the side of the body prevents the pen from rolling away. The body also features a soft rubber coating and is ergonomically shaped for writing comfort. The high-quality tip is made of nickel silver (a copper alloy with nickel also known as German silver) and gives an extremely smooth writing experience while dispensing the latest Stabilo bionic liquid ink technology.
Note: Liquid ink rollerball pens typically write wider than a similarly labelled gel or ballpoint ink pen. This 0.5 mm rollerball pen writes similarly to a 0.7 or 1.0. mm gel pen.
I really like the feel of this pen. I enjoy rubber bodied pens greatly. This
is a very well designed pen and it feels very good in the hand. The ink is dark
and there is very little resistance across the page as you write. I will agree
with other reviews I've read. This may be advertised as a 0.5 mm but the line
is much wider. Compared to say the Zebra Sarasa I'd say the line width is
between the 0.7 and 1.0 mm sizes. But I prefer bolder lines so this isn't an
issue. Just don't buy this expecting a fine line. The other big issue is that
for such a nice pen this is NOT refillable via any means. In this day an age,
and for the price this is a bit no-no! I wish Stabilo would make one of these
refillable and retractable. This would be awesome.