Love this thing but I have too many 9 mil launchers. The standard receiver has been replaced with a Nexus Evo Gen 2 Delayed Blowback Receiver making it the MP5 at home. It's got all the standard HBI upgrades in there - extended charging handle, trigger, mag release, and improved safeties (all stock parts included too). I also have 7 mags - 5x (32rds), 2x (20rds)