 The Leyland Atlantean buses ordered as replacements were the first double-deck vehicles in the fleet, and the economics of the move can be seen in that they had 72 seats, as opposed to the single deck trolleybuses with 32 seats.The Company had been the first private company to operate trolleybuses in Britain, and were also the last to do so.The Mexborough & Swinton Traction Company Limited developed closer ties with Yorkshire Traction in the late 1960s, as both companies were controlled by British Electric Traction, although British Rail held some of Yorkshire Traction's shares.