Coupling code: Blue Square
Underframe: 64ft 6in
Engines: AEC 150hp
The GRC&W Co. Ltd built 20 of these single unit railcars, to designs drawn up by Derby C&W works for the Birmingham and London areas of the WR. They were nicknamed along with the Class 121s as "bubble cars". Trailer cars were built for these vehicles, becoming TOPS Class 150, and used as loadings required.
In the 1970s some sets were re-allocated to Scotland, particularly around the Ayr area. Three of these were soon converted to Class 131 DMLVs. The other cars, except one which had entered into departmental use in 1969 were cascaded to the West Midlands based at Tyseley. They were used on local services, most notably the Leamington Spa to Stratford-upon-Avon route, also the Stowbridge Town - Jct shuttle and for fitting into formations when a car would be removed for depot or works attention.
In 1984 two cars moved to Longsight to replace life expired Class 108s on the Stockport - Stalybridge service. The same year three were transferred to Bletchley for work on the St Albans and Bedford branches.
In 1987 problems with Class 142 units on the West Country branches resulted in a reprieve for six vehicles, working the Cornish branch lines to Looe, Newquay and St Ives until withdrawal, the last two in 1993.
Many were used as route learning cars, and a number preserved.