This small part fix (lock) inner barrel in the Hop Up chamber. It is called C Clip. It is for M4 HopUp chambers. Made of nylon. Price for 4 pcs.
MAD BULL Airsoft
was established in 2004 in Taiwan. It is a world famous company that manufactures upgrade parts for AEG and GBBR’s. Madbull has licensing from real steel companies like Noveske, Troy, Stark, Vickers Tactical, Barrett, Daniel Defense and Adam’s Arms. They produce a wide variety of inner parts such as barrels, hop-ups, cylinders, springs, grips, silencers etc.