During the Showa era, when railway transportation played a leading role in logistics, railway mail and parcel transportation was carried out by mail and parcel cars connected to passenger trains. Trains began to be operated, and express cargo trains were also operated on trunk lines such as the Tokaido/Sanyo Main Line and the Tohoku Main Line.
A considerable number of freight coaches that were remodeled from old passenger coaches were arranged, and a wide variety of freight trains composed of steel mail cars, freight passenger cars for pallets, and mail passenger cars were seen.
-Mani 36 (Modified Slone 30) was born by remodeling a superior passenger car for luggage transportation. A total of 230 Mani 36s were manufactured, supporting the increasing number of parcels transported. The body color is brown.