Abstract: This invention is directed to a high performance electrical telecommunication transmission cable, particularly for undercarpet applications. More precisely, this invention is directed to a low-profile, high performance flat cable, where the cable may be subjected to potentially damaging compressive forces from walking on an overlying carpet. The cable comprises a plurality of conductors arranged as plural sets of twisted pairs, with each conductor consisting of an inner conductive core surrounded by insulation, an outer dielectric member having plural longitudinally extending chambers, where each chamber includes two sets of the twisted pairs, spaced-apart and arranged in side-by-side fashion and generally parallel. The height of the chamber is dimensioned to exceed the wrap diameter of a set of a twisted pair of conductors.