A Special diaphragm for rear of A and one end of B using the scale length drawbar, plus a diesel diaphragm for the rear of the B unit (black). 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.