Target age: 8 years old and over With this product, spoke wheels can be installed on vehicles that require current collection of passenger and freight cars (caboose, etc.). Compatible vehicles: old passenger cars, 80 series trains, caboose. (Vehicles with wheels with an axis length of 14.4 mm) Oha 35 series, Suha 43 series, Suha 32 series, 10 series, Suha 44 series, postal freight passenger car, 80 series train, Yo 5000, Yo 3500 * Older models other than 80 series It is not possible to install the Kokuden because it has a different shaft length (13.2mm). (From Discovery Japan Mall)