C Products LLC, a popular manufacturer of M-16 and AR-15 magazines, can "block" their stainless steel body magazines to limit the round capacity. After a fairly lengthy wait I finally recieved a shipment of these magazines. These are 30 round stainless steel magazine bodies that have a tab punched into each side of the body. The purpose of the tab is to restrict the movement of the follower so that no more than 10 rounds may be inserted.