USMC (United States Marine Corp) Originally called the Continental Marines, and founded in 1775 as Naval Infantry. The United States Marine Corp. operates along side the U.S. Navy and comes under the United States Department of the Navy. Functioning somewhat as naval infantry, the Marines are typically the first combat units rapidly delivered to global crisis.

USP (Universal Self-Loading Pistol) The USP is a semi-automatic pistol designed by the German arms manufacturer Heckler & Koch.

WA (WESTERN ARMS) WA is a very popular Japanese manufacturer specializing in high quality replica handguns. Established in 1976, WA has garnered a large share of the gas blowback pistol Airsoft market. Their most cutting edge GBG unit is the “Magna” or the (Most Advanced Germinate Action Device). This pistol has fascinated many enthusiasts and is patented in several countries including Austria, Canada, Spain, Japan, and the United States. They are also known for their excellent replicas of the M1911 and the Baretta M9 handguns. WA has generally licensed the trademarks on their handguns from popular manufacturers such as Colt and Beretta.

Weaver Rail Please see RIS (Rail Interface System).

Zero In Airsoft, when the trajectory of a shot is aligned with the visual line of sights.