171724 approaches Becket's Crossing, Fairfield (near Appledore) on 2 June 2013 with the 1G50 17:22 Ashford International to Brighton Southern service. This was during a very lucky few minutes of sunshine, between two very large black clouds! The Class 171s are identical to Class 170s with the exception of the Dellner coupling, which replaces the 170's standard BSI coupling. Whilst the four car units were built with the Dellner coupling, the two car sets were converted from 170s. 171724 was originally numbered 170724.