equipped with a modernised interior. The driving end was fitted with 4CEP style windows, ceiling (with fluorescent lights and luggage racks but with 3+2 Class 319 seating. Accidents and incidents On 25 February 1979, 4TC unit No. 414 formed a passenger train that was hauled by Class 33 locomotive 33 115. The train was in collision with an engineering train near , Hampshire. The crane in the engineering train was foul of the adjacent line, and a side-long collision occurred, severely damaging the locomotive and damaging all four carriages. One person was killed and nine were injured. On 12 December 1988, a train comprising 4REP unit 2003 coupled to 4TC units 8015 and 8027 formed the 06:14 - Waterloo service, which ran into the rear of the 07:18 - Waterloo train, formed of 4VEP units 3033, 3119 and 3005 at . The two trains derailed and collided with a third train, formed of 4VEP units 3004 and 3425 running in the opposite direction on an adjacent line. Thirty-five people were killed, 415 were injured. Description The units were built in two batches. In the first batch, a total of 123 locomotive-hauled Mark 1 carriage were converted comprising 63 TSO to DTSO on Lot 30764, 32 BSK to TBSK on Lot 30765 and 28 FK to TFK on Lot 30766. In the second batch, 14 locomotive-hauled carriages were rebuilt comprising 2 BSK to TBSK on Lot 30855, 6 FK to TFK on Lot 30856, and 6 TSO to DTSO on Lot 30857. This work included converting the three 3TC units to 4TC. The 1974 build units were fitted with double-glazed windows (except for the sliding toplights) as fitted to contemporary CIG/BIG stock. They also differed from the 1967 units in having the contemporary CIG/BIG style of seating throughout, as all coaches were new-build. Individual vehicle numbering is shown in the table below. Further use Following withdrawal from passenger service, several vehicles were sold for further use with London Underground. They were used primarily for special excursions trains on the Metropolitan line, hauled by either steam locomotives, or the preserved electric locomotive No. 12 "Sarah Siddons". Details of the vehicles sold to London Underground are given below. For further information, see London Underground coaching stock. Six 4TC vehicles were formed into a test train in 1994 for use by Eurostar to test the third rail pick-ups for use by the Class 373