A cable sealing component for an enclosure comprising: a pair of elastomeric sealing blocks that cooperate with each other disposed within the enclosure and operable between a sealing configuration and an open configuration; and a first pair of rib sets (220, 270; 230, 280), a first rib set of the first pair of rib sets being integral with a first of the pair of elastomeric sealing blocks, a second rib set of the first pair of rib sets being integral with a second of the pair of elastomeric sealing blocks, each of the rib sets of the first pair of rib sets comprising a plurality of flexible ribs having flexed and non-flexed positions, and a plurality of grooves (222, 272; 232, 282), the ribs of the first rib set of the first pair of rib sets occupying the grooves of the second rib set of the first pair of rib sets and the ribs of the second rib set of the first pair of rib sets occupying the grooves of the first rib set of the first pair of rib sets when the elastomeric sealing blocks are in the sealing configuration and the ribs are in the non-flexed position, characterised in that : each of the ribs comprises a notch , each of the notches has a center, and when the elastomeric sealing blocks are in the sealing configuration, a first reference line through the centers of the notches of the first rib set of the first pair of rib sets is offset from a second reference line through the centers of the notches of the second rib set of the first pair of rib sets. a pair of elastomeric sealing blocks that cooperate with each other disposed within the enclosure and operable between a sealing configuration and an open configuration; and a first pair of rib sets (220, 270; 230, 280), a first rib set of the first pair of rib sets being integral with a first of the pair of elastomeric sealing blocks, a second rib set of the first pair of rib sets being integral with a second of the pair of elastomeric sealing blocks, each of the rib sets of the first pair of rib sets comprising a plurality of flexible ribs having flexed and non-flexed positions, and a plurality of grooves (222, 272; 232, 282), the ribs of the first rib set of the first pair of rib sets occupying the grooves of the second rib set of the first pair of rib sets and the ribs of the second rib set of the first pair of rib sets occupying the grooves of the first rib set of the first pair of rib sets when the elastomeric sealing blocks are in the sealing configuration and the ribs are in the non-flexed position, characterised in that : each of the ribs comprises a notch , each of the notches has a center, and when the elastomeric sealing blocks are in the sealing configuration, a first reference line through the centers of the notches of the first rib set of the first pair of rib sets is offset from a second reference line through the centers of the notches of the second rib set of the first pair of rib sets. each of the ribs comprises a notch , each of the notches has a center, and when the elastomeric sealing blocks are in the sealing configuration, a first reference line through the centers of the notches of the first rib set of the first pair of rib sets is offset from a second reference line through the centers of the notches of the second rib set of the first pair of rib sets. <EOS>