Holland & Holland Royal De Luxe double rifle in .600 Nitro Express with 28-inch barrels, the most powerful commercially produced double rifle cartridge, reserved for the thickest-skinned dangerous game at closest range. Type: Rifle Action: Break action double Caliber: .600 Nitro Express Capacity: 2 Year introduced: 1903, UK Weight: 192 oz Overall length: 45.5" Status: Active Intended use: Elephant hunting / Collectible