Version 2.1 of the hop-up alignment system, designed specifically for M4 AEG HPA replicas using:
- PolarStar F2 engine (dual-solenoid HPA engine with preloaded spring nozzle and electronic pressure/volume adjustment).
- Bullgear 2024 chamber (new CNC hop-up version with dual adjustment system and geometry optimized for HPA).
This kit ensures precise alignment between the F2 nozzle and the Bullgear 2024 chamber, eliminating lateral play and maintaining consistent nozzle-to-chamber contact for maximum feeding consistency in demanding HPA builds.
Compatibility
| Component | Compatibility |
|---|---|
| HPA Engine | PolarStar F2 M4 / V2 |
| Hop-up Chamber | Bullgear 2024 |
| Base Replica | M4 AEG |
| Gearbox | V2 / ICS SPLIT ✓ |
What the kit includes
- Rear clip for mounting via rear pin or fixed stock.
- Base with housing for M3 inserts (optional brass).
- Side clip for routing the HPA tube/line.
- Front locking top cap designed specifically for Bullgear 2024.
- Rear plate with mounting point for an M5 screw (additional reinforcement).
Required components (not included)
- 4× M3 × 4.2 mm threaded inserts
- 4× M3 × 8 SHCS screws
Recommended products
The most recent models added to the collection



