the body of the railcar was built at petone workshops in the hutt valley; driver's compartments were located at both ends and it could carry fifty passengers. the railcar employed the thomas system of transmission, built by thomas transmission ltd. of england. they also supplied the underframe and bogies, and j. tylor and sons of london provided the railcar's v8 petrol engine. power from the engine was transmitted to the leading bogie mechanically and to the rear bogie electrically by current produced by a generator within the engine. when engine revolutions passed a certain level, the electrical system was cut and used for battery charging while special clutches and gears allowed the engine to mechanically drive both bogies. unladen, the railcar weighed approximately and its length was .