United Technologies Corporation provides technology products and services to building systems and aerospace industries worldwide. Its Otis segment designs, manufactures, sells, and installs passenger and freight elevators, escalators, and moving walkways; and offers modernization products to upgrade elevators and escalators, as well as maintenance and repair services. The company's Carrier segment provides heating, ventilating, air conditioning, refrigeration, fire, security, and building automation products, solutions, and services for commercial, government, infrastructure, residential, and refrigeration and transportation applications. This segment also offers building services, including audit, design, installation, system integration, repair, maintenance, and monitoring. Its Pratt & Whitney segment supplies aircraft engines for commercial, military, business jet, and general aviation markets; and provides aftermarket maintenance, repair, and overhaul, as well as fleet management services. The company's Collins Aerospace Systems segment provides electric power generation, power management, and distribution systems; air data and aircraft sensing systems; engine control, intelligence, surveillance, and reconnaissance systems; engine components; environmental control systems; fire and ice detection, and protection systems; propeller systems; engine nacelle systems; aircraft lighting, seating, and cargo systems; actuation and landing systems; space products and subsystems; avionics systems; flight controls, communications, navigation, oxygen, and training systems; food and beverage preparation, and storage and galley systems; and lavatory and wastewater management systems. The company offers its services through manufacturers' representatives, distributors, wholesalers, dealers, retail outlets, and sales representatives, as well as directly to customers. United Technologies Corporation was founded in 1934 and is headquartered in Farmington, Connecticut.