The basic infantry weapon of the U.S. Marine Corps is the M16 assault rifle family, with a majority of Marines being equipped with the M16A2 or M16A4 service rifles, or more recently the M4 carbine a compact variant. Suppressive fire is provided by the M249 SAW and M240G machine guns, at the squad and company levels respectively. In addition, indirect fire is provided by the M203 grenade launcher in fireteams, M224 60 mm mortar in companies, and M252 81 mm mortar in battalions. The M2 .50 caliber heavy machine gun and MK19 automatic grenade launcher (40 mm) are available for use by dismounted infantry, though they are more commonly vehicle-mounted. Precision fire is provided by the USMC Designated Marksman Rifle (DMR), which is being replaced by the M39 Enhanced Marksman Rifle, and M40A3 sniper rifle.