101 was the first of Hull's celebrated "Coronation" trolleybuses and seems to have been brought of the nearby depot for the benefit of the photographer.
The box visible behind the front offside window upstairs is a periscope. Part of the design brief of these vehicles was that they should be capable of operation by one person, even though it was not legal for double-deckers when they were built, in fact not until after they were all scrapped!
