the british rail class 373 or tgv-tmst train is an electric multiple unit that operates eurostar's high-speed rail service between britain, france and belgium via the channel tunnel. part of the tgv family, it has a smaller cross-section to fit within the constrictive british loading gauge, was originally able to operate on the uk third rail network, and has a lot of fireproofing in case of fire in the tunnel. this is both the second-longest——and second-fastest train in regular uk passenger service. in 2015, the new eurostar class 374 (e320’s) started being rolled out making the class 373’s going for scrap. as of 2017, 11 sets remain in service. in 1997, great north eastern railway (gner) ordered a few trains for use on the ecml and were retired in 2005. tgv hired these trains on their lines. as of 2016, all units remain in storage with no plans to return to service. these trains also ran on third rail towards london waterloo. as of 2017, all but a few tgv tmst’s are in new eurostar blue livery.