Unique coach RDB977091 was built by British Leyland as an experimental prototype incorporating Leyland bus body parts on the underframe of former BR Mk1 BCK M21234. The coach was a regular feature of Brighton to Manchester cross country services and is seen here at Reading in the formation of the 0920 from Brighton. I rode this coach a couple of times and whilst the seats weren't very comfortable it was bright and airy.
The coach is preserved on the East Kent Railway at Shepherdswell.