In the late 1930's, Waddington's, who manufactured Monopoly games in London and Leeds for Great Britain, also produced an accessory to the game in the form of a Monopoly money note holder. The money was to be held in place using rubber bands to secure the scrip to these boards with small strips of cardbaord to hold the money in place. The set above did have some old rubber bands with it, but they were rotten and are not shown. Seems a bit clunky, but it must have sounded like a good idea at the time. I do not believe these were produced after the start of WWII, only from 1936 - 1939 or 1940.