It was built on the Panzerkampfwagen 38(t)?s widened and lengthened chassis with modified suspension (larger road-wheels from Praga TNH n.A prototype reconnaissance tank) and up-rated engine. The new engine was 160 PS Praga AC/2 6-cylinder engine controlled by Praga-Wilson gearbox (5 forward and 1 reverse gear). Chassis was modified in order to accommodate larger gun and thicker armour than regular Panzerkampfwagen 38(t) tank. Its combat weight was 16 metric tons (versus 9.8-tonnes for the Pz 38(t) and it could travel at maximum speed of some 42 km/h.