The Bendix® AD-HF® (High Flow) PuraGuard® oil coalescing air dryer and the AD-HFi® (High Flow Intelligent) air dryer collect and remove air system contaminants in solid, liquid, and aerosol form before they enter the brake system. As a module, they provide heavy vehicles with an integrated vehicle air dryer, purge reservoir, governor, and a number of the charging valve components in a complete assembly. These components have been designed as an integrated air supply system.