These new WABCO air compressors, purchased as an overstock item, are genuine OE units manufactured in Germany and tested at Arnott. Each compressor comes completely assembled with mounting brackets and air lines and is ready to bolt in. This complete unit will cost you a great deal more at your Mercedes-Benz dealership! It is common for air compressors to burn out because of a leak in an air suspension spring, leaving your air suspension on the ground. Once installed, Arnott recommends checking your system for leaks.