The U.S. Ordnance M16A4 Rifle features a performance identical to the M16A2. Physical differences between the two weapons include a removable carrying handle with an integral rail mounting system on the M16A4. When the carrying handle is removed, any accessory device with a rail grabber, such as an optical sight, can be mounted on the weapon. Firing 5.56 x 45 mm NATO ammunition, it is a gas-operated, air-cooled, magazine-fed, selective-fire weapon with a fixed length stock. Its selective fire options include semi-automatic and “ full auto.” The U.S. Ordnance M16A4 Rifle barrel is designed to accommodate the M203 Grenade Launcher that can be assembled to the rifle easily, offering the user both point and area firing capabilities. Also, all U.S. and NATO rifle grenades can be fired without any supplementary equipment. The M16A4 rifle 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, Advanced Optical Gunsight (ACOG) and M68 Aimpoint. EOTech holographic weapon sights are part of the SOPMOD II package.