It is a derivative of the Class 375 Electrostar designed specifically for use on the high-volume metro routes running south-east from London, England. The changes are mostly focussed on increasing the trains’ capacity and decreasing the time they must spend stopped in station. The Class 376’s doors are wider to allow more passengers to board at once, and are metro-style sliding doors which are faster and more reliable than the Class 375’s plug doors, although they do not provide as much insulation for heating and cooling purposes. Also, no air conditioning is provided, with hopper style windows available for ventilation. In order to provide more standing room, the trains also have fewer seats, more handrails, and no on-board toilets (South Eastern promised to provide additional facilities