Original: However, they also have significant differences, such as fully longitudinal seating similar to that used on London Underground rolling stock to give more standing room, which is necessary for the high passenger volume metro-style services expected to be run on London Overground.
Simplified: Primarily,  the Class 378 will feature fully longitudinal seating similar to that used on London Underground rolling stock, which is necessary for the high passenger volume services expected to be run on London Overground.