Mercedes Benz Vito Taxi

In August 2008 a variant of the Mercedes Vito was approved by the Public Carriage Office for use as a licensed London 'black cab'. The Vito taxicab includes sliding doors, electric steps and seating for six people. The Vito's rear-wheel steering enables it to meet the PCO's strict 25 ft (7.6 m) turning circle rule and it is able to carry two wheelchairs. The vehicle, a variation of the 'Traveliner' model, will be produced by EcoCity under licence from Mercedes-Benz, and distributed through its KPM-UK Taxis subsidiary.

All of these vehicles have to conform to the conditions  of fitness as set out by the PCO (Public Carriage Office).

The Public Carriage Office (PCO)

Public Carriage Office
The Public Carriage Office (PCO) is the body responsible for licensing taxicabs within Greater London. The PCO is part of Transport for London and is responsible for licensing the familiar London taxicab or "black cab" and also licenses private hire or minicab services. Since 30 March 2007 the actual processing of licences has been outsourced to a private company called SGS.
 
PCO licence plate, as seen on the back of all licenced hackney carriages (September 2006)Since 1600 public carriages for hire have been a feature of London life. The discarded coaches of aristocratic families, complete with their coat of arms, were among the first hackney carriages to ply for hire. They were the forerunners of the French hackney carriage or cab (cabriolet) which first appeared in London around 1820.