They make aftermarket parts with the trademarks and stuff.

Mine is a gas blow back with a poly lower and metal slide it weighs about the same as an unloaded glock (2.1lbs IIRC?). Its pretty neat me and some friends used to play pistols only in an abandon apartment complex.

Its pretty sweet I can hit a fence post from 30 feet 8 out of 10 shots (usually get 2-3 flyers every 10 rounds or so depending on the weight of the bb).