4P-020-421 GWR Toplight Mainline City GWR All Brown Composite 7909 Set 5The first order for these coaches was placed in 1915 but, due to the First World War, they were not built until 1920. The second batch was completed in 1921. Six sets of coaches were produced with each set comprising six coaches. The coaches were close coupled and constructed with a steel body rather than the traditional wooden panelling. Due to the restrictive loading gauge of the London Underground tunnels, the carriages are 7 inches lower than