BRAND NEW. NEVER USED. Zion Arms brand V2 metal gearbox. Took it out of a Zion Arms R15 as soon as I bought it. Compatible with all rifles that take a v2 gearbox. Perfect condition. No issues. Never opened. Metal shell. Nebula programmable mosfet can be programmed for different firing modes including safe, semi, full auto, binary, 2 round burst, and 3 round burst. Quick change spring. Deans battery connector. Motor leads are in perfect shape. Wanting to sell or trade. Willing to bundle with anything else I have listed.