A filter for venting an enclosure (1) containing an electrical apparatus (4), such as a lens or lighting unit of a motor vehicle, and exposed to moisture or atmospheric agents, the filter including a tubular body (20) with a through cavity or conduit (11) opening at opposite ends (9, 10) of the body (20), which is coupled to a venting aperture (6) of the enclosure (1), the filter (8) including a hydrophobic filtering element; the body (20) of this filter (8) includes at least two portions (20A, 20B) set at an angle to each other, the membrane filtering element (15) being in the interior of the body (20) and being associated with it in such as manner as to form one piece therewith, and being coupled to the body (20) in a manner transverse to an axis of at least one of the portions.