Irvine Martin branded 15w red lacquered lamp

From what I can remember, Irvine Martin was quite a reputable brand here in the UK (which I believe still exists) that supplied large-scale outdoor lighting equipment, particularly Christmas lights for town councils, etc. I'm not sure who actually made this lamp but I suspect it was Crompton. Interestingly the lamp etch states "Irvin" when their website states "Irvine" instead - probably a mistake on the part of the lampmaker!