Alexander Dennis Enviro500

The Alexander Dennis Enviro500, first sold as the TransBus Enviro500, is a three-axle double-decker bus built in the United Kingdom, unveiled in 2002 as one of the Enviro series. Its Dennis chassis, also called the Trident E500, was modified from the Trident 3 and used Cummins engines with Voith or ZF gearboxes, while the body was based on the original single-deck Enviro300 style. It was sold with diesel or hybrid-electric powertrains, and as bodywork on Volvo chassis. Initially only a 12 metre version was made, with a 12.8 metre version added in 2007 and an 11.3 metre version in 2008, and Hong Kong was the first city to use it. The Enviro500 MMC superseded it in 2014.