Early Met-Camm 2-car sets
Introduced : 1955 Coupling Code : Yellow Diamond
Body : 57ft x 9ft 3in Engines : BUT (AEC) 150hp
Transmission : Standard mechanical  

It was in August 1955 that the first lightweight diesel railcar produced by Metropolitan-Cammell emerged from the Washwood Heath works at Saltley in Birmingham, this was the precursor of what was to become the largest fleet of diesel multiple units built for service on BR, with a further 339 already on order by the time the last car was delivered in July '56.

The cars were ordered in May '54, as part of the then £2,000,000 programme for the development of lightweight diesel trains on British Railways.

Integrally constructed using steel and light alloy, 72 cars were built to form 36 power trailer sets. Seven sets were for the LMR to be used mainly on Bury - Bacup services, and twenty-nine sets for the ER for East Anglia. While all cars were externally identical, the cars differed internally depending on what region they were destined.

Being a non-standard coupling code, their incompatability meant an early withdrawal, by 1969.