The Commer Q4 “Bikini” FV13100 is a militarised version of the civilian Commer Centrepoise. It has a 6-cylinder, 4750cc, petrol engine and four wheel drive. Its task with the Auxilliary Fire Service (AFS) was to provide water for fire pumps. It carried several Coventry Climax fire pumps, which were floated on dinghies in a river or lake and provided an extra water supply for land based pumps. The Museum’s 1958 vehicle is rare, only one other working example being known in Britain. Many Q4s were used by the army in the immediate post war era and were fitted with several different types of bodies, from Command Workshops to Signals offices.