Constructed of from a durable, patented composite, these magazines will withstand the toughest corrosive environments. The clear polymer magazine body allows you to monitor your ammunition status. Hardened steel inserts dummy rounds and heat-treated chrome silicon wire spring provide maximum reliability and smooth feeding. A front mounted grip supports quick and easy reloading. The package includes an Operator s Manual, Carrying Pouch, Graphite Lubricant and Loade Technical Specifications Weight 1.5lbs Color Black/Clear Compatible with AR-15 / M16 / M4 Caliber .223 / 5.56mm x 45mm Capacity 50 rounds Body Material Polycarbonate Spring Material Leaf spring