MR556 A4 5.56 16.5" 10+1 BLK Manufacturer Model Number: 81000828 Manufacturer: Heckler and Koch (HK USA) Model: MR556 A4 Caliber: 223 Rem | 5.56 NATO Type: Rifle Item Type: Firearm Firearm / Accessory Action: Semi-Auto Firearm / Accessory Capacity: 10 + 1 Finish: Black Sights: No Sights Stock Frame Grips: Collapsible / Folding Stock HK416 Slimline Furniture Magazine Quantity and Description: 1 10 rd. Overall Length: 33.25" to 36.5" Weight: 7.67 lbs. Shipping Weight: 14.65 Feature: Short Stroke Gas Piston Feature: HK416 Upper Receiver Feature: M-LOK Handguard Optic Adjustable Objective: false Optic Reticle Illuminated: false