Design for this wheel was guided by the two principles of simplicity and durability. The wheel rolls easily over the most difficult terrain and can stand up to constant heavy use. No spokes in the wheel means brush and debris won't get caught in the wheel, which makes it great for cross country. Wheel has 4' circumference and 15 1/2" dia. Measures in feet & inches. Folds to half its size. Wheel has 6 year warranty. Made in the USA.