Colt Sporter 223 - 5.56mm 30 Round Magazines are made of mil-spec materials and are manufactured under strict, ISO quality control standards. The heat-treated, welded aluminum body is hard-anodized for superior corrosion resistance. The black finish keeps the magazine from giving off a glare. Treat your gun to the highest quality magazines on the market. The weight of each magazine is 0.250 pounds.