The JK is Zebra’s skinny gel refill. It is most commonly found in Zebra’s G-301 gel pen.
This is a good refill, but generally is not used in top gel pens. It is a useful refill because its short length and narrow diameter mean it is easy to modify for use in pens that don’t have gel refills available, like Fisher Space Pens.
Zebra JK Gel Pen Refill Information
|Rollerball / Gel
|Max Body Width
|Refill Length (cm)