X40はSJ(スウェーデン国鉄)最新の近郊電車です。近郊電車と言っても、用いられるのは駅間10-20分の都市間の普通列車(Reg)です。先代のX50に比べ、二階建てを採用して定員の増加が図られたほか、ドアが低床部に設けられ、車いすもリフト無しで乗降できます。二階建てながら、機器室は最小限に抑えられ、しかも最高速度は200km/hです。今後も増備が進むでしょう。
X40 is SJ's newest suburban electric train. Although called suburban, it is used on interurban Reg local services with 10 to 20 minutes between stations. Compared with its predecessor X50, it uses a double-deck body to increase capacity, with doors in the low-floor sections so wheelchair users can board without a lift. Despite the double-deck design, equipment compartments are kept to a minimum, and maximum speed is 200 km/h. Further purchases are expected.