This is a completely custom built lvoa. No problems what so ever and is so appealing! Get the performance and looks an Umbrella Armory lvoa but for the price of G&G gun. I'm down with trades! warsport top hat compensator! 20 rps w/ 7.4 lipo Internals: Perfectly shimmed Lonex gear box shell with steel bearings, SHS gears, Gate mosfet, Lonex high torque motor,Lonex air nozzle, Lonex cylinder and cylinder head, Lonex piston and piston head, ProWin hop up with Prometheus flathopped purple bucking and bridge-type nub.