Class 506 EMU '01' at Reddish Electric Depot on 30 January 1981, with driving trailer M59601M nearest the camera. The 'M' suffix denotes that it's an LMS number, not a BR number, and there was also a BR 59601. Curiously the suffix should be 'E' as the 506s were an LNER design and numbered in the LNER series, not the LMS.