Lettering based on the London Underground 1986 Stock Passenger Information System, specifically, the 'red' train.
Lettering based on the Great Western Railway (GWR) 'Thames Turbo' Class 165 and 'Thames Express' Class 166 Passenger Information System.
Based on the lettering used for London Underground S Stock trains (S7/S8 Circle, District, Hammersmith & City and Metropolitan lines).
Based on the lettering used on the London Underground Northern Line 1995 Stock Passenger Information System.