The Combat Machine GR16 Carbine is G&G Armament's entry level airsoft gun. Modeled after the M4 carbine, it is very well put together and dependable. Built in Taiwan instead of China, this entry level gun is a great alternative to Echo 1 or JG AEGS. The body and most major external parts are very durable reinforced plastic. The barrel assembly, carry handle, and buffer tube are an aluminum alloy. The internals are factory upgraded with hardened gears, high tension spring, 8mm oilless bearings, and a 25000 rpm hi-torque long axis motor. The included magazine is G&G's standard 450 round real size high capacity magazine. Replacement magazines abound, so never fear! The battery compartment is located in the forearm of the rifle and is accessed by pulling down on the delta ring and pulling off the lower half of the handguard. Airsoft players love and recommend this gun as a great alternative to China-made AEGs. A great performing rifle for an affordable price!