The disclosure provides a passive pressure drag reduction apparatus. The apparatus comprises a housing (106) comprising a base face (114), an open top face (110) opposite the base face and at least one side face (108) extending between the base face and the top face, wherein the base face, the top face and the at least one side face define a cavity (102). A panel (112) is aligned with the top face of the housing, and there is provided an aperture (104) extending around the panel, wherein the cavity is in fluid communication with an environment surrounding the apparatus via the aperture. Further, attachment means are provided arranged to secure the panel to the housing.