I don't know but it seems like it's an ACM clone of the ARES/STAR/S&T Quick Change spring. From what I can tell it's made by like Action/Army/Element or some other ACM clone company.
tl;dr It's a standard gearbox that's cloned the quick change spring feature.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE