A new remote control cable (11) has a core (39) with a jacket (43) made of nylon 12 having polytetrafluoroethylene as a constituent. The "gap" between the cable core (39) and the cable conduit (45) is decreased compared to corresponding prior art cables and the thickness of the core jacket (43) is about three times that of corresponding prior art cables. Core column strength is about doubled. The cable (11) is equipped with a new dynamic sealing device (10) made of a thermoplastic polyurethane. Such device (10) has a pair of sealing ridges (69, 71) of differing diameter which bear against a rod (37a) moving with respect to the cable conduit (45). The outer ridge (69) excludes airborne contaminants and the inner ridge (71) retains a synthetic lubricant (53).