This is a rare USGI Air Force rimfire conversion magazine for the M16 or AR-15. It features white nylon construction, 10 round capacity of 22LR ammo and is designed to hold the bolt open when empty. The original conversion and it's magazines were developed by U.S Air Force Master Sergeant Julius V. Jurek, the conversion had a rifled chamber insert, and was gas-operated. The magazine you will receive is still in the unopened packaging as seen in the last image, the label is dated 12/80. The magazine shown here is representative of what you will receive with your purchase. Finding these magazines still in the original sealed packaging is incredibly rare. Buy online today!