This AF4756/AF4757 air filter is the engine air intake filter element for Dongfeng heavy trucks. It filters dust, sand and debris in the intake air, delivers clean air to the engine combustion chamber, protects engine cylinders, pistons and other core components from abrasive wear, reduces engine failure and extends service life. Adopts high-efficiency filter paper with good dust holding capacity and stable air permeability. The rubber sealing ring has good sealing performance to prevent unfiltered air from entering. Each air filter passes air permeability and dust holding test before delivery. It is an essential replacement spare part for truck engine intake system maintenance.