In 1927 a pair of railmotors was ordered from Shefflex Motors Ltd., who operated out of Tinsley in Sheffield. These were delivered to the Selsey Tramways (by then the West Sussex Railway). Shefflex was a manufacturer of lorries and trucks, and their chassis was used as a basis for the units.

They were a better design than the Ford vehicles, but still suffered from many problems whilst in service. They were slightly larger than the Ford units, and in the same way as the Ford, were coupled back to back and had a luggage trailer alloted to them.

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