Cristal
Used by 2 peopleen.wikipedia.org ↗

“I love a Bic Biro to both write and draw with.”
Robyn Lees-West Interview, Textile taxidermist · via Uses This 
“For sketching, I use Bienfang 4x4 and 10x10 cross section graph paper and Bic Cristal black ballpoint pens.”
Greg Wohlwend Interview, Game designer (Hundreds, Gasketball, Solipskier) · via Uses This