Abstract: The response of middle distillates to flow improvers can be substantially improved by utilizing a dual-functioning flow improver composition which is a combination of two different wax modifying compounds. One of these functions as a wax growth arrester. The other functions as nucleating agent. Specifically, for example, it has been demonstrated that a copolymer of ethylene with vinyl acetate in combination with another copolymer of ethylene with vinyl acetate where either the vinyl acetate monomer is present in different proportions and/or the molecular weights are different is a flow improver combination which imparts significant improvements in the filterability of middle distillate fuels.