The standard 4-inch Model 10 was the most common police sidearm in the United States from the 1920s through the 1980s. Its round-butt and square-butt configurations served virtually every American law enforcement agency. Type: Revolver Action: Double-Action Caliber: .38 Special Capacity: 6 Year introduced: 1899, USA Weight: 33.5 oz Overall length: 9.25" Status: Active Military use: Yes Intended use: Duty, Service, Sport