Magpul Mag1183-MCT PMAG Gen M3 10+1/30+1 223 Rem/5.56 Nato Fits AR/M4 Black Polymer The PMAG 10/30 AR/M4 Gen M3 Is a 10-Round Polymer Magazine For AR15/M4 Compatible Weapons chambered In 5.56X45 Nato/.223 Remington. It Was Designed For users Who Reside In areas With Magazine Capacity restrictions But Desire a Standard 30-Round Magazine Form. Caliber: 223 Rem/5.56 Nato Capacity: 10+1 Model: PMAG Material: Polymer Capacity: 10+1 Manufacturer: Magpul Industries Corp Mfg Number: Mag1183-MCT Model: PMAG Series: Gen M3