Parker G2 Refill
Pens, Inks & Leads · 7 specs
Direct Answer
The Parker-Style G2 Refill (standardized under ISO 12757-2 Doc G2) is one of the most widely adopted ballpoint and gel pen refill standards. Measuring 98.1 mm in length and 5.8 mm in body diameter with a stepped metal barrel and grooved plastic crown cog, it is used by hundreds of luxury pen brands and custom machined EDC pens.
Source: ISO 12757-2:1998 (Ball point pens and refills — Part 2: Documentary use) / DIN 16554 · Last reviewed Aug 28, 2026
Specs
| Overall Length | 98.1 ± 0.3 mm (3.86 in) |
| Main Body Diameter | 5.8 ± 0.1 mm (0.228 in) |
| Stepped Tip Diameter | 2.5 mm extending 18.0 mm from barrel shoulder |
| ISO Standard Code | ISO 12757-2 Type G2 (Documentary permanence proof) |
| Crown Cam Geometry | Molded nylon cog crown with 4 radial guide splines for push-button advance mechanisms |
| Available Ink Formulations | Oil-based ballpoint (Parker QuinkFlow, Schmidt P900), hybrid low-viscosity (Uni Jetstream SXR-600), gel ink (Schneider Gelion+, Itoya) |
| Pen Brand Compatibility | Parker, Pelikan, Faber-Castell, Rotring (600/800), Retro 51 Tornado, Tactile Turn, Karas Kustoms |
The Universal Luxury Standard
First engineered by the Parker Pen Company for the landmark 1954 Jotter ballpoint, the G2 format's physical dimensions and crown mechanism became the open global benchmark (formalized as ISO 12757-2). It allows pen enthusiasts to swap classic oil-based pastes, ultra-slick Japanese hybrid inks (Uni Jetstream SXR-600), or ceramic rollerball refills (Schmidt easyFLOW 9000) inside the exact same pen body.