Having taken Alexander ALX400s on B7TL chassis for the 10, the 23 also received ALX400s, but on Transbus Trident chassis. They replaced Routemasters. TNA33368 (LX53EJY) is negotiating the revised layout at Trafalgar Square.
Original London Sightseeing Tour Volvo B7TL East Lancs Visionaire VLE617 (LJ07XEU) rounding Marble Arch in Spring 2008 in company with First Transbus Trident ALX400 TNA33349 (LK53FCJ).