The Nitro Max stands out and stands supremely comfortable with our premium NITRO™ technology built right in. This lightweight combination of flexibility and support cushions and stabilizes the foot for optimal performance. Nitro Max Tall Riding Boot Product Features : 0 : NITRO™ stabilizing frame for support with forefoot flexibilityShock Shield® diffuses heel strike impact to minimize fatigue, 1 : Premium full-grain leather upper with oiled inner calf panel, 2 : Removable NITRO™ insole for shock absorption and rebound, 3 : Duratread™ sole with rider-tested traction zones, 4 : Full-length elasticized panel on lateral side, 5 : Mobility notchLightweight chassis for heel and mid-foot torsional stability, 6 : Full lengthpremium quality coiled YKK® zipper Men's Nitro Max Tall Riding Boots in Black, Size: 9 D Medium Slim by Ariat