[2] The KiHa 141 cars are powered by one DMF13HS 250 hp (190 kW) engine, and retain the original toilet of the 50 series coaches.

[2] The KiHa 142 cars are powered by two DMF13HS 250 hp (190 kW) engines, and the original toilet of the 50 series coaches was removed during rebuilding.

[3] 11 KiHa 143 cars were built in 1994 from surplus 50 series OHaFu 51 locomotive-hauled coaches to provide additional capacity on the Sassho Line.

[3] The fleet of KiHa 143 cars is scheduled to be replaced by new 737 series AC electric multiple units from spring 2023.

[3] Four KiSaHa 144 non-powered intermediate cars were built in 1994 from surplus 50 series OHaFu 51 locomotive-hauled coaches.

[3] A large number of locomotive-hauled 50 series coaches became surplus to requirements following electrification of lines in the Sapporo area of Hokkaido in the late 1980s.

A program was therefore started to rebuild a number of these coaches into diesel multiple unit (DMU) trains to replace ageing DMUs on the non-electrified Sassho Line.