Product Description SPECIFICATIONS MATERIAL: NYLON POLYMER CAPACITY: 2,500 ROUNDS CALIBER: 6 MM COMPATIBILITY: MOST M4 AND M16 AEGS COLOR: BLACK MANUFACTURER: SENTINEL GEARS FEATURES DURABLE LIGHTWEIGHT POLYMER CONSTRUCTION SOUND CONTROLLED AUTO-WINDING TECHNOLOGY. HIGH-CAPACITY MAGAZINE HOLDS 2,500 ROUNDS OF BBS. C-MAGAZINE DESIGN. COMPATIBLE WITH MOST M4/M16 AEGS WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov/product Customer Reviews