 British Rail Class 357

The British Rail Class 357 Electrostar alternating current (AC) electric multiple units (EMUs) were built by Adtranz at its Derby Litchurch Lane Works, England, in two batches from 1999 to 2003 at a cost of approximately £292 million.They were the first member of the Electrostar family, which also includes Classes 375, 376, 377, 378, 379 and 387, and are the most numerous type of EMU built in the post-privatisation period of Britain's railways.