Durango? X-Pand System? The Durango X-Pand System is a hidden gore expansion for a universal fit and easy on/off. Square toe Rolled shank area 1 1/4" Rocker heel Full-grain leather with ventilated shaft to promote maximum air flow Air mesh lining Cushion flex insole with rigid rear foot stabilizer 3/4 genuine Goodyear? welt construction Genuine leather welt with double row cotton stitch Durable and rigid nailed ABS heel Littleway shank stitch for ultimate durability