ProMag AR-15 42 Round Tan Features A magazine for AR-15/M16 rifles and carbines the magazine body and follower are constructed of a proprietary DuPont Zytel based polymer to ensure a long service life. The springs are made from heat treated chrome-silicon wire for increased reliability and smooth feeding. ProMag AR-15 42 Round Tan Specifications Brand: ProMag Category: Magazines Caliber: .223 Rem. 5.56 NATO Capacity: 42 Round Color: Tan Material: DuPont Zytel Polymer Firearm Fit: AR-15 Style: Detachable