A small build, these coaches had shallow (10¼”) window vents They were used specifically in two coach sets with a semi-open brake third (Comet Models S8S). Operating as through portions from Waterloo, they were detached at a junction to be taken on to their final destination, often behind an M7 0-4-4T. Resorts such as Bude, Ilfracombe, Padstow, Seaton, Sidmouth and Torrington were thus served. Equipped originally with the Prestall centrally mounted vacuum cylinder and 2′ diameter vacuum reserve cylinder, between 1951 and 1958 they were converted to the more conventional arrangement of two vacuum cylinders with ‘V’ hangers and 1’6″ vacuum reserve cylinders. In some cases the original equipment was simply disconnected but left in place.