Alder Valley was the amalgamation of the old Thames Valley Traction Company and Aldershot and District, my father drove for them at the Reading depot… The bus is an ex A&D Dennis Loline, similar to the Thames Valley Traction Bristols, but Bristols could only be purchased by National companies (like Thames Valley and BRS etc) so Dennis made a rather poor substitute for private buyers. Reading Corporation Transport had a fleet of them as well.
Pete.