Part of the TGV family , it has a smaller cross-section to fit the smaller loading gauge in England , it was originally able to operate on the UK third rail network , and it has extensive fireproofing in case of fire in the 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 .