The Breda engine 2 H 88 derives from a project originally designed by the French engineer Roland Laraque in the 1940s, then built by the Manufacture d'Armes de Paris (M.A.P.) from 1947 to 1950 for the DR3 agricultural tractor. In Italy the engine was produced under license by Breda Motori up to 1959, for the Ansaldo Fossati FB4r tractor. From a technical point of view, the engine works according to the two-stroke Diesel cycle, and it is endowed with a Roots supercharger. The engine features a particular compact arrangement made with only two horizontal cylinders. In each cylinder two opposing pistons work, connected to the crankshaft through two connecting rods and a central rocker arm. The intake and exhaust ports are machined at the ends of each cylinder, near the lower dead centres of each piston stroke. This allows the exhaust gases discharge by means of an efficient unidirectional current flow.