The 50 series general-purpose passenger car was born in 1977 for the purpose of replacing the old passenger car, improving transportation and improving safety. The conventional narrow manual passenger door has become a wide automatic door, and the area around the doorway has also become a long seat, greatly improving the convenience and safety of getting on and off. Nicknamed "Red Train" from the car body painted on Red No. 2, it was heavily used for commuting to school in the suburbs of local cities.