Alexander Dennis is a Scottish bus building company based in Larbert, Scotland. The largest bus and coach manufacturer in the United Kingdom, Alexander Dennis has manufacturing plants and partnerships in Canada, China, Europe, Hong Kong, Malaysia, New Zealand, Singapore, South Africa and the United States. In early 2016, Alexander Dennis had a 44% market share in the United Kingdom. Alexander Dennis was acquired by Canadian bus manufacturer and former joint venture partner NFI Group in May 2019.
The entire vehicle is switched to ZF axles, and the drivetrain system is arranged to the left to provide a flatter platform and is more compatible with EU Type 6 engines and even hybrid technology. The new chassis is named "Trident E500 Turbo" with codename E50D (D refers to diesel, Diesel; the hybrid version is named "Trident E500 Hybrid" with codename E50H, and H stands for Hybrid), also launched two lengths of 11.3 meters and 12 meters. The 12-meter version is further subdivided into the Airport Specification and the ordinary version.