BR Class 401

The Southern Railway (SR) gave the designation 2-BIL to the DC third rail electric multiple units built during the 1930s to work long-distance semi-fast services on the newly electrified lines from London to Eastbourne, Portsmouth and Reading. This type of unit survived long enough in British Rail ownership to be allocated TOPS Class 401.

The 2-BIL Classification meant: 2-car Bi-Lavatory stock.

Preservation
Only one 2-BIL unit has survived into preservation, namely number 2090, formed of carriages 10656 and 12123, which is in the care of the National Railway Museum, York. This unit is also one of only two pre-war main line EMUs in existence, which are still in original formation. The other is the Class 503, which is kept at the Locomotive Storage Ltd facility in Margateundefined.