One of my favourite exhibits at the RAF Museum is this Crossley light tender, built on the chassis of the Crossley 20/25 chassis which was also used as a staff car (see the thread on the Shuttleworth Collection for a photo of one). The first one was delivered to the Royal Flying Corps in 1913 and by the end of the war there were 6000 in service. By 1922 there was still 328 in service, and as well as serving in the UK and Western Front, they were also used in India and Mesopotamia (Iraq). After the war many were sold off, and the nickname of the 'Flying Squad' in the Police force comes from the fact that the London Metropolitan Police force formed the Mobile Patrol Experiment in 1919, it was equipped with two Crossley Tenders from the Royal Flying Corps
Interestingly, the modern display board on the Crossley has an older style one next to it now, which correctly states it was a 15cwt tender, whereas the modern one states it as 34cwt several times, for some unknown reason