D&H Tactical is a manufacturer of precision aluminum and steel firearm magazines and a proud supporter of the Second Amendment. They metal stamp magazines from aircraft grade aluminum or premium steel on large tonnage mechanical presses, progressive form and then fuse with spot welding automation. Each and every magazine is checked for key critical characteristics. Destructive tests are periodically performed to verify weld adhesion. Magazines are then heat-treated and hard coat anodized for maximum wear resistance. A 17-7PH spring tested for spring "set" and compression values guides a precision ammunition follower. Features: 4 Round Standard Heat Treated Aircraft Aluminum Black Teflon - Hard Coat Anodized 17-7PH Spring for Ultimate Protection Against Corrosion D&H Proprietary Follower for "Big Bore" Cartridges