The Class 112 and Class 113 DMUs used the standard Cravens body used on Class 105s but had a single Rolls-Royce C8NFLH engine rated at 238 hp (177 kW) per car, all of which formed into 'power twins'- two car sets with both vehicles powered.There were two batches built, the first 50 vehicles (25 sets) had standard mechanical transmission via a gearbox and were allocated the Class 112.