In September 1963, at the time when the original single bore Dartford Tunnel opened, the Dartford Tunnel Joint Committee (DTJC) had to provide a method of conveying cyclists and their cycles through the tunnel since cyclists were not allowed to ride independently through the tunnel.

Five Ford Thames Trader truck chassis with double deck bus bodies specially built by Strachans were acquired for the purpose. The upper deck provided the seating and the lower deck was fitted with cycle racks which were loaded alongside a platform.

The buses were operated by London Transport on behalf of the DTJC and carried fleet numbers TT1-5 with registrations 526-530 FJJ.