Retro Arms CNC Upper Gearbox for ICS EBB M4 Airsoft AEGs

Specifications

• Precision machined from a block of billet EN AW 7075 T651 aluminum
• Quick change spring guide system (spring guide sold separately)
Reinforcement in key stress points to counter rapid wear from high performance parts
• Pre-radiused cylinder windows - helps evenly distribute impact force
• Compatible with ICS EBB Series M4 Airsoft AEG Rifles