KWA KM4 2GX. It has since been modded into a Block II configuration. This thing has been used heavily and has finally just begun giving me issues. Doesn't feed reliably on a new, full mag, but on half a mag it runs like a dream. Don't have the time nor energy to continue trying to fix it. I have put in a new tappet plate which seemed to help. I have my suspicions a new air nozzle will fix it. The rear of the lower receiver has a hairline crack in it which I've had for years, shouldn't impact performance. Either way, I'm moving on to an HPA setup and this must go! Build List: KWA Stock KWA upper & lower receiver 2GX gearbox SHS 13:1 gears SHS High Torque Motor Stock cylinder Upgraded piston & piston head. New m120 included, stock spring still installed. (Has settled nicely to around 380ish last time I checked.) Lightweight Outer barrel KAC NT4 Flash Hider Madbull licensed DD RIS II Stock brass inner barrel & hop up w/ G&G green bucking Rewired to 16AWG wiring w/ deans connectors Stippled A2 grip. Cash only - not looking for trades.