A device for connecting an electric wiring harness to the rear of an electrical connector, includes two half-shells configured to be assembled and to receive within them at least one cable of the electric wiring harness, a rear clamping nut designed to compress the two half-shells radially around the cable, a longitudinal body designed to hold the two half-shells axially, a front clamping nut designed to hold the longitudinal body around the electrical connector, wherein each one of the two half-shells includes an inner pad made of an elastomeric material, configured to be in contact with the cable, and an outer jacket made of a rigid material, at least partially enveloping the inner pad and configured to be in contact with the rear clamping nut.