Kadee Quality Products Co. • Compatible with Kadee® #1-Scale Couplers. #1905 AAR Type "E" Couplers, "Prototype" Head Centerset Couplers & #779 Gear Boxes. #1906 AAR Type "E" Couplers, "Prototype" Head Centerset Shank Couplers & #1920 (#820) Body Mount Gearboxes.