The British Rail Class 485 (or 4Vec, later 5Vec) and British Rail Class 486 (or 3Tis, later 2Tis) electrical multiple units were originally built for the London Electric Railway from 1923-31 as its 'Standard' tube stock.

At the time of their purchase the units had already worked for over 40 years on the London Underground, but their introduction allowed the last steam locomotives on the line to be withdrawn.

[8] Due to the proximity to the sea, the units suffered badly from corrosion damage.

However, several 485 vehicles were sold back to London Underground for eventual restoration as part of an operational 'Standard' stock museum unit.

During November 2011 the two long-stored DM vehicles 2 and 7 were despatched by LU to Eastleigh depot for component recovery and subsequent breaking up: this is believed to have occurred in December 2011 (although this has not been confirmed).