This is a spare wheel from a lunar roving vehicle (LRV). The LRV was deployed on the moon during Apollo 15, 16 and 17. The tire is made of a woven mesh of zinc-coated piano wire to which titanium treads were riveted in a chevron pattern. This pattern kept the wheels from sinking into the soft lunar soil. The lunar soil proved harder than expected and the wheel treads left tracks about half an inch deep.Transferred to the National Air and Space Museum from the Alabama Space and Rocket Center in 1975.