Timberland EarthKeepers Chukka boots have a smaller environmental footprint than other footwear. Timberland EarthKeepers design-pioneering, outdoor-tested shoes like this Earthkeepers Chukka boot are made with one or more major components containing at least 50% recycled P.E.T. - the plastic used to make pop bottles. The upper of the Timberland Earth Keepers Chukka boot is made premium waterproof burnished nubuck leather uppers for comfort, durability and abrasion resistance and has a shock distribution system that creates a pressure-reduced zoned impact footbed. The Smart Comfort biorhythmic system brings comfort and support while the shock-absorbing construction of the chassis, midsole and outsole reduces shock to eliminate leg and foot fatigue. This Timberland Chukka boot does not contain PVC.