Parts ListUpper Receiver and Barrel Assembly | 1 | Handguard Assembly | 6 | Ring, Retaining | | 2 | Pin, Gas Tube | 7 | Spring, Slip Ring | | 3 | Gas Tube | 8 | Ring, Slip | | 4 | Compensator | 9 | Upper Receiver Assembly | | 5 | Washer, Compression | 10 | Barrel Assembly |
Front Sight Assembly | 1 | Post, Front Sight | 4 | Pin, Front Sight Housing | | 2 | Detent, Front Sight | 5 | Rivet, Sling Swivel | | 3 | Spring, Front Sight | 6 | Sling Swivel |
Upper Receiver and Rear Sight Assembly | 1 | Rear Sight Assembly | 7 | Aperture, Rear Sight | 13 | Spring, Elevation Knob | 19 | Spring, Ejection Port Cover | | 2 | Pin, Windage Knob | 8 | Spring, Flat, Aperture | 14 | Screw, Index, Elevation | 20 | Ejection Port Cover | | 3 | Windage Knob | 9 | Base, Rear Sight | 15 | Index, Elevation | 21 | Pin, Forward Assist | | 4 | Spring, Windage Knob | 10 | Pin, Sight Base | 16 | Knob, Elevation | 22 | Forward Assist Assembly | | 5 | Ball, Windage Knob | 11 | Spring, Elevation | 17 | Ring, Retaining | 23 | Spring, Forward Assist | | 6 | Screw, Windage | 12 | Ball, Elevation Knob | 18 | Pin, Ejection Port Cover | 24 | Upper Receiver |
Forward Assist Assembly | 1 | Pin, Retaining, Pawl | 4 | Spring, Pawl | | 2 | Pawl | 5 | Plunger, Forward Assist | | 3 | Detent, Pawl | | |
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Weapons 
