6mm ARC Magazine 5 Rounds Stainless Black by ASC- These ASC 6mm ARC magazines are Stainless Steel, engineered with the highest levels of quality for increased longevity, simply the best in the industry! Our magazines are manufactured 100% start to finish in the USA using .020 gauge 410 Stainless Steel Alloy, heat treated for superior strength and lasting endurance. Our magazines are chemically treated for corrosion resistance [ref QQ-P-35] and coated with our proprietary finish, Marlube which is a wear-in not wear-off coating that burnishes into the surface providing self-lubricating properties. - Compatibility... These mags fit and function in Mil Spec AR-15 firearms that are chambered for the 6mm ARC cartridge.