Prometheus Perfect Metal Hop Up Chamber NEO Set for Marui M4/M16 AEG

Prometheus Perfect Metal Hop Up Chamber NEO Set for Marui M4/M16 AEG Metal Chamber & Polymer Parts Suitable For Tokyo Marui M4/ M16 Series Airsoft Electric Gun AEG Rifle Stabilizes the muzzle velocity and fits tightly to the barrel base, hence the chamber can always aligns to the center.