The history and physical detail of these coaches is quite complex. The first four were bow ended designs to diagram H26. In the same lot were two flat ended coaches to H27 and H28, differing only in the 1st class seating arrangements. The remaining four to H29 were given bow ends. The coaches were rebuilt during the 1930s and received modern integral sliding vents in place of the toplights. The etch depicts this rebuilt style and all coaches had similar side profiles. In the late 1930s some (including both of H27/H28 and 9574 of H29) had their 4 wheel bogies replaced by 6 wheel. In 1948 the coaches were refurbished internally and were long lived, remaining on premier services until the last withdrawal in 1961. No. 9575 unusually received BR chocolate and cream livery in 1956 and was used in the Torbay Express.