The Model 642 Airweight Centennial is the best-selling revolver in Smith & Wesson history. The stainless steel cylinder and barrel on an aluminum alloy frame deliver corrosion resistance with extreme light weight at 15 ounces. Type: Revolver Action: DAO Caliber: .38 Spl +P Capacity: 5 Year introduced: 1990, USA Weight: 15 oz Overall length: 6.3" Status: Active Intended use: Carry, Backup