Another overview from Mach 1 Airsoft, covering the ASG STI Duty One CO2-powered Airsoft Pistol... "The DUTY ONE is fully licensed by the famous high-end small arms manufacturer, STI International, based in Texas, USA. The pistol is semi-automatic and based on the classic model 1911 but STI has upgraded and changed the design and many of the functions. The frame has an integrated front waiver rail for mounting light and laser.