碓氷峠
Sixteen 7-car sets (112 vehicles) including one Green car were delivered between 1980 and 1981 to Shin-Maebashi depot to replace ageing 165 series EMUs. Compared with the earlier 185-0 series sets, these had cold-region specifications, including snow-resistant brakes, front-end horn covers, and were able to operate over the Usui Pass between Yokokawa and Karuizawa in conjunction with JNR Class EF63 electric locomotives. Livery was white with a single green band running the length of each car below the windows. The first trains were introduced on express services such as the "Kusatsu" and "Karuizawa" from December 1981.