HO Diaphragm for 3 locomotive (gray). For A-B-B or A-B-B-A lashups. Close the gap with our innovative injection molded operating diaphragms. This easy to assemble kit turns a diesel lashup into convincing scale power units. Diaphragms stay connected in turn radii over 24 inches and have no minimum radius for smooth operation. Use with Kadee® #5 or similar Couplers. Instructions are included with all kits.