Replacement O-Ring Gasket for Bolt Action Pen by BASTION® - Choose Size

All current Bastion standard and Slim bolt action pens use the classic Parker-style G2 refill, also known as the ISO G2 or International G2 format.

This is not the same as a Pilot G2 refill. Some wider third-party Parker refills may also have fit issues, so Bastion replacement cartridges are recommended for the most reliable fit and smooth operation.

• View the Ink Refill Guide
• View the Slim Pen Refill Guide
• Watch Ink Refill Installation

Changing the refill is simple and does not require any tools.

1. Retract the writing tip.
2. Unscrew the front section of the pen.
3. Remove the old refill and set the small spring aside.
4. Place the spring over the writing end of the new refill.
5. Insert the new refill and screw the front section back on until snug.
6. Test the bolt action and write a few lines on paper.

If the refill feels stuck, does not retract, or creates resistance in the bolt action, remove it rather than forcing the mechanism. Confirm that it is the correct Parker-style G2 size or use a Bastion replacement cartridge.

• View the Ink Refill Guide
• View the Slim Pen Refill Guide
• Watch Ink Refill Installation

You can find replacement ink cartridges, pocket clips, clip screws, springs, tips, O-rings, bolt pins, and selected mechanical-pencil parts. They’re useful for replacing a lost component or keeping a favorite Bastion pen working properly.

- Visit Pen Parts Collections

Not always. Some components may differ between regular and Slim Bastion pens. Choose the size or style listed for your model, or contact our Support Team with a photo of your pen if you’re unsure.

Choose standard ballpoint ink for a familiar, dependable everyday writing feel. Choose gel ink if you prefer a smoother flow and richer-looking lines. Bastion replacements are available in black and blue.

Most replacement parts are designed for straightforward installation. Ink cartridges and springs can usually be changed without special tools, while clips and screws require a T-6 Torx driver and a little more care.

The kit includes one replacement pocket clip and two M2.5 screws with T-6 Torx heads. Clip options are available in stainless steel or titanium, depending on the selected style.

The factory screws use threadlocker to keep them secure. Warm the area gently with a hair dryer to loosen the seal, remove the screws with a T-6 Torx driver, and use a small drop of threadlocker when installing the replacement clip.

Consider replacing the spring if it is lost, bent, or no longer retracting the cartridge smoothly. Before ordering, check that the refill is the correct size and that the spring is seated on the writing-tip end.

Yes. These smaller Bastion pen parts are available separately, so you can replace the missing or worn component without replacing the entire pen. Be sure to select the correct type or size for your model.

Contact our Support Team with the name of your pen and a clear photo of the part you need. Confirming the model first is the easiest way to avoid ordering the wrong replacement.

Yes. We currently ship international orders to Canada, the United Kingdom, and Australia.

International orders follow the same fulfillment schedule as domestic orders. Once the order has been fulfilled, the estimated delivery time depends on the shipping service selected at checkout:

• Standard shipping: 6 to 14 business days
• Express shipping: 2 to 5 business days

If you have questions about international shipping or an existing order, please contact our Support Team.