The British Rail Class 207 (3D) diesel-electric multiple units were built by BR at Eastleigh in 1962.

The Southern Region class 201 to 207 DEMUs are nicknamed 'Thumpers' due to the distinctive sound of their engines.

[2][3] When new the class were used on the Oxted Line, and were mostly concentrated on services between London Victoria and Uckfield and Eridge to Tonbridge via Tunbridge Wells.

[4] Most units were withdrawn in 1987 following the electrification of the Oxted Line's East Grinstead branch.

[5] Four of the seven surviving units were used on the Reading to Basingstoke Line between 1988 and 1993; once this had finished three were withdrawn and the fourth sent to join the other three survivors on the Marshlink Line;[4] between 1995 and 1998 this included through services from Ashford International to Brighton.