The Arnott Air Suspension Compressor P-3258 for the Mercedes-Benz 2012-2018 ML-Class (W166) and 2013-2018 GL-Class (X166) is a direct replacement for the original OE compressor from Mercedes-Benz. The Arnott compressor is manufactured using quality components and is built to OE specifications. This maintenance-free compressor is extensively tested by Arnott engineers to assure durability along with OE like performance, functionality and fit. This compressor is assembled with vehicle-specific mounting brackets and reuses the factory isolators and mounting hardware for a fast installation. This replacement Mercedes compressor comes with an integrated air dryer unit, new relay, thermal overload protection, and mates perfectly to the OE electrical connectors, airline fitting, and intake hose.