Westinghouse Air Brake Technologies (dba Wabtec) manufactures braking equipment and other parts for locomotives, freight cars, and passenger railcars. Products made by Wabtec's Freight group include air brake systems, draft gears, hand brakes, slack adjusters, heat exchanges, railroad electronics, and monitoring and control equipment. Wabtec's Transit business supplies replacement parts and repair services to operators of passenger transit systems. Major customers have included Trinity Industries, General Electric Transportation, Union Pacific, and CSX Transportation. The company traces its roots back to 1869, when inventor George Westinghouse first demonstrated his straight air brake in 1869.