A cable connector adapter comprising a segment of tubular elastically deformable flexible conduit, having an outside surface of helical convolutions, connected to a cable connector boot having an integrally formed oval female threaded nut into which the conduit is screwed in a deformed, oval configuration. The conduit is deformed into an oval shape to fit and screw into the oval threaded female nut, said deformation flattening the conduit and adapting it to the generally rectangular shape of the boot and connector, thereby providing the transition in the shape of the bundle of conductors of the cable from round substantially rectangular.