Electrostatic powder coating apparatus comprising a spray module located within a bight of a conveyor having suspended from it a plurality of articles to be coated with powder prior to heat treatment to convert the powder into an adherent coat of paint or the like.The spray module comprises a veined impeller able to rotate about a vertical axis and having charged powder projected towards its center from a stationary nozzle so that vanes on the impeller impart centrifugal force to the powder particles.The impeller and nozzle assembly may be reciprocated vertically so that the sprayed powder traverses the length of the suspended and moving articles.