Alliant Techsystems Inc. (ATK) is an aerospace, defense, and commercial products company that operates in 23 states, Puerto Rico, and internationally. The Company is a producer of military small-caliber ammunition for use in soldier-carried weapons, such as automatic and semi-automatic rifles, and machine guns. ATK is also one of the producers of medium-caliber ammunition used by crew-served weapons on armored vehicles and aircraft. It is a producer of military large-caliber ammunition used by tanks. In addition, the Company is a producer of ammunition for the sport enthusiast and law enforcement markets. ATK is a manufacturer of solid rocket motors, supporting tactical, strategic, missile defense, and space launch applications. As of March 31, 2011, ATK's four operating segments are Aerospace Systems, Armament Systems, Missile Products, and Security and Sporting. In April 2010, ATK acquired Blackhawk Industries Products Group Unlimited, LLC.