https://airsoftgogo.com/product/we-open-bolt-system-g39e-gas-blowback-rifle-w-bipod/
WE Open-bolt system G39E Gas Blowback rifle w/ bipod - AirsoftGoGo - Quality Gear, Trusted Value
Oct 17, 2024 - Production Description Manufacturer: Taiwan New designed Open-bolt system Non-copper gas tube inside the bolt again !!! Foldable Bipod integrated with Nylon