The first ADL Enviro 400 MMC (Major Model Change) was built in 2014 with the first entering service in London during 2015. Since then the type has been available as an integral, the E40D diesel and hybrid E40H model. A number of Volvo B5LH models also entered service with London operators. The MMC became one of the standard London double-deck types, becoming popular with Go-Ahead London, Stagecoach London and Abellio London.The Enviro 400 City followed in 2018, the hybrid version proving less-popular than the Enviro 400 MMC. Arriva London and CT Plus took stock of the hybrid E40H model, with no others being purchased. However, the type came into its own when the body was fitted to the BYD D8UR DD electric double-decker in 2018.London's Enviro 400 MMC and City takes a look at the history of the two types since their introduction up until the present day.