The commander has a 12.7mm Browning M2 machine gun and the loader has a 7.62mm M240 machine gun. A 7.62mm M240 machine gun is also mounted coaxially on the right hand side of the main armament.
The M1A1 tank incorporates steel-encased depleted uranium armour. Armour bulkheads separate the crew compartment from the fuel tanks.
The top panels of the tank are designed to blow outwards in the event of penetration by a HEAT projectile. The tank is protected against Nuclear, Biological and Chemical (NBC) warfare.
One L8A1 six-barrelled smoke grenade discharger is fitted on each side of the turret. A smoke screen can also be laid by an engine-operated system.
In August 2006, General Dynamics Land Systems was awarded a contract to produce 505 tank urban survivability kits (TUSK) for the US Army Abrams tanks. TUSK includes add-on reactive armour tiles, loader's armour gun shield (LAGS), tank infantry phone (TIP), Raytheon loader's thermal weapon sight with Rockwell Collins head-mounted display and BAE Systems thermal driver's rear-view camera (DRVC). TUSK entered service on M1A1 / M1A2 tanks in late 2007 and has been deployed to Iraq.More information about General Dynamics is available online at www.generaldynamics.com.