OKAY helped co-develop the original 30 round M16 magazine with the U.S. Military in 1973. Together we engineered a military marvel that delivers every round, from every rifle, every time. Battle-tested OKAY magazines earned their reputation as the best USGI versions available. Perfect for any Mil-Spec AR-15 modern sporting rifle, SureFeed magazines give you one less thing to worry about. Reliability rules when youre choosing a magazine. So we put each and every SureFeed magazine through a multi-step inspection and testing process. Our proprietary quality control ensures every SureFeed magazine lives up to its name and remains true to the OKAY performance heritage trusted by the U.S. Military since 1973. SureFeed magazines are 100% made in the U.S.A., with all-American components that meet or exceed demanding Military Specifications. The magazine bodies & floor plates are lightweight aluminum, heat treated to Mil-Spec requirements for strength and durability. Theyre hard-coat anodized and finished in your choice of a Mil-Spec dry film lube grey or Tactical Black PTFE. A four-way, anti-tilt, self-lubricating, non-hygroscopic resin follower and high performance Mil-Spec stainless steel spring keep rounds properly aligned and tensioned for flawless performance.