These are Kadee® Conversion Bolsters for AHM 4 Wheel Passenger Trucks FEATURES: Precision engineered with prototypical details. These bolsters (brackets) are for the 4 wheel truck mounted coupler pockets on AHM (Rivarossi) passenger cars. Truck mounted couplers permit closer coupling on radii down to 18" without causing binding for most passenger cars. Made in the USA. INCLUDES: (2) #508 Bolsters (2) #5 Couplers Mounting Hardware REQUIRES: Assembly Kadee® #522 Non-Magnetic Wheels (KADU0522) Non-Magnetic trucks should be used with Kadee® Magne-Matic® Couplers (KADU0003 or KADU0005) kr1/3/07