The Smith & Wesson Model 645 is a usa-made double-action pistol chambered in .45 ACP, introduced in 1985. Primary use: self_defense, law_enforcement. Type: Pistol Action: Double-Action Caliber: .45 ACP Capacity: 8 Year introduced: 1985, USA Weight: 29 oz Overall length: 8" Status: Discontinued Intended use: self_defense, law_enforcement