68032 hauls a rake of Mk5 coaches near Crewe in December 2018. © Mark Watson
The Class 68 is a mainline mixed-traffic diesel-electric locomotive manufactured by Stadler Rail (and previously Vossloh Espana) for Direct Rail Services in the UK. The design is based on Stadler's existing "Eurolight" platform, with this variant being known as the "UK Light". The locomotives are highly capable for a variety of work across the UK, including use on heavy freight trains, nuclear flask workings as well as passenger operations. A number of the fleet are sub-leased to Chiltern Railways and TransPennine Express hauling Mk3 and Mk5 coach sets respectively. Two members of the class also worked on ScotRail's FIfe Circle Route, hauling Mk2 coaching stock, but due to the stock not meeting PRM-TSI regulations they ceased operation in 2020.
(Information provided by Wikipedia)