Among the toughest and most dependable polymer AR-10 magazines on the market, Lancer’s L7 series features steel feed lips to ensure reliable feeding and a stainless steel front guard to maximize rigidity. Completely designed and manufactured in the United States, the L7 is available in either opaque or translucent models. The latter allow the shooter to visually confirm how many rounds remain in the magazine without removing it from the gun. Price: $50. Contact: Lancer Systems; (610) 973-2600; lancer-systems.com.