EQUIPMENT DESCRIPTION: SEAT MODELS 6800/338 AND 6800/348 SUPPLIED BY ISRINGHAUSEN FOR USE ON TRANSIT BUSES. THE TETHER PLATES, WHICH ARE ATTACHED TO THE REAR OF BOTH THE UPPER AND LOWER FRAMES OF THE SUSPENSION UNIT, CONTAIN A SHARP EDGE WHICH CAN CAUSE PREMATURE WEAT OF THE NYLON TETHERS.