L415 (51393, 59503 & 51351) passes White Waltham on 6 January 1991 with the 2F33 10:40 Paddington to Reading Network SouthEast service. 1991 would be the last full year that these venerable Pressed Steel units had the virtual monopoly of these trains. Introduced over three decades earlier, they had spent their entire life on the route. Originally in green livery, they were later painted blue, white and blue, blue and grey, and they finally ended up in this colourful paint scheme.