Display apparatus having a rail fixable on a stationary structure and provided with a groove, a sliding member fittable in the rail groove and slidable therealong, a wire or cord coupled to the sliding member, a gripping member through which the wire or cord passes, a supporting hook connected to an end of the wire or cord remote from the gripping member, and a second rail having a groove for receiving the hook such that the wire or cord is coupled to the second rail and is tensioned when installed. The gripping member through which the wire or cord passes, comprises a hollow member having an inner tapered surface, a sleeve member having a passage formed therein for the wire or cord and situated within the hollow member to be freely slidable with respect thereto with at least a portion of the sleeve member projecting out from the hollow member, and at least one ball captured in the sleeve member seating against the tapered inner surface of the hollow member and communicating with the passage. A spring urges the sleeve member in a direction in which the inner surface of the hollow member tapers.