PolarStar F2 Direct Attachment + PolarStar HopUp · Alignment Kit V2.1 · M4 / AR15 AEG

3D Printing Parameters

• Approximate print time: ~1 hour 30 minutes
• Recommended material: PLA+
• Layer height: 0.10 mm – 0.15 mm

Manuals

Installation and adjustment manuals are available in the Manuals section of the website or on the project's Discord server.

Installation and Adjustment

1. Printing and Preparation

• Print the parts with 65% to 80% infill.
• Lightly sand the internal and contact areas to improve the fit.
• If necessary, apply dry lubricant or wax to the sliding surfaces.

2. Installation on the Replica

• Insert the base into the lower receiver and install the M3 inserts.
• Install the rear clip aligned with the rear pin or fixed stock.
• Install the PolarStar HopUp chamber with the inner barrel.
• Guide the F2 HPA line through the side clip to prevent rubbing or sharp bends.

3. Final Adjustment

• Secure the rear plate using an M5 screw and washer for maximum rigidity.
• Check that the PolarStar F2 nozzle enters the chamber correctly and remains centered.
• Perform dry tests and adjust the hop-up according to the BB weight.

Recommended Lower Receiver

For maximum rigidity, we recommend using an ICS metal lower receiver.

If you prefer to 3D print your lower receiver, the following Gearbox V2 Lower "Universal Lower" models are compatible:

• Version 3
• Version 4.2
• Version 4.3 MTW

You can find them HERE.