An apparatus for conditioning compressed air comprises a generally cylindrical body 1 housing a filter unit 5, a pressure regulating unit 8 and a lubricating unit 10 arranged in end-to-end relationship with one another. In use, compressed air to be conditioned enters the apparatus via a pipe fitting 14, passes sequentially through the units 5, 8 and 10 and is piped to a point of use via a pipe fitting 14'.
Apparatus of the invention dispenses with the need for conventional depending filter and lubricator bowls and is thus relatively compact and streamlined compared to traditional designs.