0.5 mm refill for the Energel Tradio Gel Pen by Craft Design Technology.
Drehgriffel No. 1 Gel Pen Refill - Black
$ 5.00
Kaweco G2 Gel Rollerball Refill
$ 7.00
Ohto Gel Refill .5mm - Black
$ 2.00
Parker Gel Refill Black Medium