The Model 640 Centennial is a fully concealed-hammer (DAO) stainless steel J-Frame chambered in .357 Magnum. The enclosed hammer offers snag-free draw from any carry position. It revives the Centennial concept in stainless steel. Type: Revolver Action: Double-Action Only Caliber: 357 Magnum Capacity: 5 Year introduced: 1990, USA Weight: 22.4 oz Overall length: 6.3" Status: Active Intended use: Concealed Carry