David Brown evaluated the Allis Chalmers model G when they designed the DB 2D tool carrier.
They tried several twin cylinder engines but found them noisy and vibrated through to the operator. DB came up with their own unique engine - twin cylinder but with extra dummy cylinder powering downwards to smooth out the vibrations.
Ploughs, ridgers, cultivators & hoes were some of the implements that could be mounted under the frame. This one has mounted crop sprayer.
DB designed lift cylinders which ran on compressed air powered by a compressor mounted on the engine.
There was a limited market for these tool carriers in Britain, used on market gardens who grew vegetables. Just over 2000 were built.