The U.S. Ordnance M16M4 carbine is a shorter and lighter version of the M16A2 assault rifle. Firing 5.56 x 45 mm NATO ammunition, it is a gas-operated, air-cooled, magazine-fed, selective-fire weapon with a 4-position telescoping stock. Its selective fire options include semi-automatic and “ full auto.” The M16M4 carbine is designed to accommodate an M203 Grenade Launcher. It is maneuverable and more convenient to carry than a full-length rifle, making it ideal for close-quarters combat (CQC), and airborne and special operations. Like all of the variants of the M16 assault rifle, the U.S. Ordnance M16M4 carbine can be fitted with many accessories, such as night vision devices, laser pointers, telescopic sights, bipods, the XM26 LSS shotgun and anything else compatible with a MIL-STD-1913 Picatinny rail. Other common accessories include the AN/PEQ-2, Aimpoint CompM4, Advanced Combat Optical Gunsight (ACOG), and EOTech holographic weapon sights.