Allison Transmission Holdings, Inc., together with its subsidiaries, designs, manufactures, and sells commercial and defense fully-automatic transmissions for medium- and heavy-duty commercial vehicles, and medium- and heavy-tactical U.S. defense vehicles. It offers transmissions for various applications, including distribution, refuse, construction, fire, and emergency on-highway trucks; school, transit, and hybrid-transit buses; motor homes; energy, mining, and construction off-highway vehicles and equipment; and wheeled and tracked defense vehicles. The company offers 13 transmission product lines with approximately 100 product models. It markets its transmissions under Allison Transmission brand name and remanufactured transmissions under ReTran brand name. The company also sells branded replacement parts, support equipment, and other products necessary to service the installed base of vehicles utilizing its transmissions, as well as defense kits, engineering services, and extended transmission coverage services to various original equipment manufacturers, distributors, and the U.S. government. In addition, it designs and manufactures hybrid-propulsion systems for transit buses. Allison Transmission Holdings serves customers through an independent network of approximately 1,400 independent distributor and dealer locations worldwide. The company, formerly known as Clutch Holdings, Inc., was founded in 1915 and is headquartered in Indianapolis, Indiana.