a safety liner for protecting the tubeless tires is provided . the liner is combined a predetermined number of segment of identical shape to form a circular configuration for disposing in place into the drop center of a tire rim and adjustably locked up by a coupling member at the confronting ends of the circular configuration . a wedge plate slidably secures between each segment and the drop center at one side and a cushion runner disposes between the circular configuration and the drop center at the other side . when the tire becomes flat , the flexible outer surface of the liner engages with the inner surface of the tire that permits a vehicle continuous operation . because the liner is combined by a plurality of segments , it is structurally flexible to suite to different types of tire rim and because the segments are in identical shape , it facilitate a mass production and low cost to manufacture .