United Technologies Corporation is engaged in providing high technology products and services to the building systems and aerospace industries around the world. The Company operates through four segments: Otis; UTC Climate, Controls & Security; Pratt & Whitney, and UTC Aerospace Systems. Its Otis segment designs, manufactures, sells and installs a range of passenger and freight elevators, as well as a line of escalators and moving walkways. Its UTC Climate, Controls & Security segment, is the provider of heating, ventilating, air conditioning (HVAC) and refrigeration solutions. The Company's Pratt & Whitney segment supplies aircraft engines for the commercial, military, business jet and general aviation markets. Its UTC Aerospace Systems segment is a provider of aerospace products and aftermarket service solutions.