The round-butt 2.5-inch stainless Model 66 was the most concealable configuration of the Combat Magnum platform. Federal agencies with shoulder-holster protocols specifically requested the round-butt variant to reduce the gun's outline in a holster worn under a jacket. Type: Revolver Action: Double-Action Caliber: .357 Magnum Capacity: 6 Year introduced: 1972, USA Weight: 35 oz Overall length: 7.5" Status: Discontinued Intended use: Carry, Plainclothes, Backup