This boot is designed with X-treme A.C. ventilated shaft that promotes air flow. The Durango X-pand system provides a customized fit with easy on and off, while the X-treme Comfort footbed with memory foam cushions the feet for maximum comfort. Moreover, the Dually Shank system delivers increased stability and Durango Easy Fit System ensures a universal fit. Part of the Durango Lady Rebel Pro Collection Durango X-Treme A. C. ventilated shaft Durango X-pand system X-treme Comfort footbed with memory foam Fiberglass Dually Shank system Durango Easy Fit System Air mesh lining Rolled shank area Cushion Flex insole Goodyear welt construction Leather welt with double row cotton stitch Durable and rigid nailed ABS heel Oil and slip-resistant outsole.