This .450 Bushmaster 5-round magazine is made using .020 gauge 410 stainless steel alloy and heat treated for strength and durability. The magazine is then chemically treated for corrosion resistance and coated with a proprietary Marlube finish that will not wear off and burnishes into the surface to provide self-lubricating properties. It includes chrome silicon springs and an enhanced anti-tilt black polymer follower. The interior dimensions of OAL 2.316 +/- .002 are perfect for new ammunition and reloads.