Retro Arms CZ Billet CNC Upper Gearbox Shell w/ Quick Change Spring for ICS M4 / M16 Series Airsoft AEG

Features

• Precision machined from a block of billet EN AW 7075 T651 aluminum
• Quick change spring guide system
• For ICS M4 Airsoft AEG
• Durable anodized finish
• Reinforcement in key stress points to counter rapid wear from high performance parts
• Pre-radiused cylinder windows - helps evenly distribute impact force

Unlike most other gearbox shells on the market, the Retro Arms CZ gearbox shells are precision CNC machined out of a solid block of billet EN AW 7075 T651 aluminum giving them unmatched durability and resilience. Combined with reinforcement of key stress points and stainless steel connecting bolts, the gearbox shell has undergone extensive stress tests with M160 springs without any signs of wear.

Retro Arms gearboxes feature a quick-change ball-bearing spring guide mechanism, allowing spring swaps in a matter of minutes without complete gearbox disassembly.

Specifications:

Compatibility: For ICS M4 / M16 Series Airsoft AEG
Material: CNC Billet EN AW 7075 T651 Aluminum
Package Includes: Upper gearbox, Quick-Change spring guide