The foundational P220 Nitron — original single-stack .45 ACP in standard black Nitron finish. Launched in 1975, the P220 established SIG's reputation in American LE and military markets. Type: Pistol Action: DA/SA Caliber: .45 ACP Capacity: 8 Year introduced: 1975, Germany Weight: 29.4 oz Overall length: 7.05" Status: Active Military use: Yes Intended use: Service, Personal Defense