Citybus Dennis Dragon 10.3metres Trolleybus ( #701 ) In March 1999, the Citybus announced that a trolleybus trial, costing HKD 5 million, will be conducted to study its feasibility for Hong Kong. Such trial involves the construction of a test track with an overhead wire network at the Wong Chuk Hang depot, and the conversion of a regular diesel bus into the world's first double-deck air-conditioned trolleybus. Based on the transmission design and specification of the chassis, it is found that the Dennis Dragon 10.3-metre is the most suitable for performing such conversion. The trolleybus is converted from Dennis Dragon 10.3-metre, #701, manufactured in 1993, bodied with a Duple Metsec bodywork assembled by Caetano of Portugal. The roof structure had to be strengthened to take the extra load from the boom equipment and the brake resistors. As much as possible of the original bus had been retained. Ref.: Citybus Limited, The Green Solution - Trolleybuses for Hong Kong.