This is 28mm Gaming scale. From what I'm told anyways. These tires were designed for FUD, BUT these may also work for FD material, but the tread is still way too fine for WSF. Can't be helped. These tires have full tread, and it needs to be seen to enjoy. Due to copy casters out there, this set was made with the tread pattern all going the same way, to make it harder for copy casters to steal our hard work.