One reason India is buying the Russian T-90 tank is the 9M119 (AT-11) anti-tank missile that can be fired via the tanks 125 mm smooth bore tank gun. The missile weighs 52 pounds, has a range of 100-4,000 meters and uses semi-automatic laser beam guidance system (the gunner keeps his sight on the target and the missile homes in on that.) Maximum time of flight is about 12 seconds. While the missile has a tandem warhead, making it useful against tanks with reactive armor, it can also be used against helicopters. The missile warhead can penetrate about 700mm of armor. The guidance system is quite accurate, hitting the target 80 percent of the time at maximum range in tests. The guidance system is also easy to use, making less well trained crews more effective.