Hitachi monorails use quad-load tire bogies. Each train car has two of these bogies. Note in this picture that there are "emergency wheels" in front of and behind the load tires and below the guide tires in case of tire failure. The bottom of the car is 1.13m (44.5") above the beam to accommodate the bogies. Suspension is provided by twin airbags. Thus, there are 8 load tires and 12 guide tires per car. Each car weighs about 11 metric tons.