Compared to other aluminium gearboxes

FPS Range: 340-370

and will not fit in the HK416 platform

Magazine Capacity: 22rds

grip and upper receiver seperatley

SHS Bore-up cylinder set for M4 AEG Handguard Compared to other aluminium gearboxesEssential part for upgrading your Airsoft Electric Gun AEG Durable cylinder with Polished Inner surface guarantee smooth action As always, upgrading AEG require necessary skill & technique to dissemble the gearbox, consult expertise if needed Package Includes: 1. Stainless Bore Up Cylinder Head 2. Bore Up Air Seal Nozzle 3. Bore Up Ventilation Piston Head 4. Bore Up Chromium Plating Cylinder Bore Up Cylinder Set need to be used with M120 ~ M170 AEG