Cable closure including grommet having enhanced sealing capability

A closure (20) includes a grommet (50) having passageways (52-52) therethrough for allowing cables to extend into the closure. The grommet (50) comprises a unitary elastomeric body (60). Each passageway is defined by an interior sidewall from which a plurality of longitudinally spaced circumferential ridges (74-74) extend. For a substantial portion its circumference, each ridge has an axis of projection which forms an oblique angle with respect to a longitudinal axis of the associated passageway and is sufficiently elongated in longitudinal cross section so as to be capable of flexing with respect to the axis of projection during insertion of a portion of a cable and enlarging its opening diameter to accommodate and form a seal about the inserted cable portion. A slit (71) which is parallel to a longitudinal axis (73) of an associated passageway extends between end faces (62,64) and from the associated passageway to an outer surface portion of the grommet to facilitate insertion of a portion of a cable into the associated passageway. The grommet also includes a plurality of ribs (69,69) on an outer surface portion which provides a seal with a surface of an opening in which the grommet is disposed. Provisions are made to cause portions of each ridge and rib adjacent to each slit to be maintained with at least some overlap during installation and use of the closure in order to maintain the sealing effectiveness of the grommet.