The Model 37 Airweight is the aluminum-alloy-framed variant of the Model 36, reducing weight by approximately 5 ounces for a revolver that can be carried all day without fatigue. It introduced featherweight revolver technology to American law enforcement and civilian carry. Type: Revolver Action: Double-Action Caliber: .38 Special Capacity: 5 Year introduced: 1952, USA Weight: 13.5 oz Overall length: 6.25" Status: Discontinued Intended use: Carry, Plainclothes