In 1989, the first 'Steam on the Met' event took place, and London Underground, hired British Rail coaching stock for the excursions. It was found that it was actually cheaper to buy the coaches instead of hiring them. Thus, London Underground has acquired numerous former British Rail coaching stock for these special excursion trains on the Metropolitan Line, usually hauled by either steam locomotives, or the preserved electric locomotive No. 12 "Sarah Siddons". The fleet consisted of several Mark 1 and Mark 2 vehicles, and eight former British Rail Class 438 electrical multiple unit trailer set vehicles. The two coaches bought in the late 1980s were initially painted in red, white and blue of LUL. After the acquisition of more coaches in 1992, all vehicles were painted in the maroon liver