The Treadmill is a collectible item in the Jet Setter Collection.
There is a 3% chance of acquiring it when collecting rents from the Skyscraper Condos, Glass Condos, Atrium Lofts, Penthouse Tower, Eco House, Eco Skyscraper, Cubic Modular, Stepped Skyscraper, Skyrise Heights or Infinite Towers I.