Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Tyre tread for use on soft sand or snow - has series of grooves sepd. by ridges which have hemi-spherical recesses with total area within specific ratios to total contact area
Vehicle with low-pressure pressure-sensitive caterpillar-type tire equipment for running on smooth surfaces has cleats in one or more channels in the inside of its tires connecting to a device for generating low pressure