LASS 319s were built for the new cross-London link between the Midland Main Line and suburban stations on the former Southern Region. The successful power door Mk. 3 steel body shell platform with inner gangways was used for the new units, fitted with a distinctive flat-fronted cab which was an improvement over the Class 317. Although the Midland Main Line (Midland suburban) was energised in January 1981, the dual voltage Class 319/0 design did not enter traffic
