Boot Sizing: Measure around leg halfway between the knee and fetlock Small = under 7" Medium = 7" to 8" Large = 8" to 9" Extra Large = 9" to 10" The PRO H40 Skid Boot was designed with the Reiner in mind. Using orthopedic grade neoprene, cut to fit snugly just above the hoof, you get a boot that really keeps the dirt out. Matched hook and loop surfaces mean this boot won’t wear out prematurely. Burn protection is provided by an extra thick rubberized wear pad which is flexible enough to conform to the leg without any hard points that might irritate. Machine washable. Sized small, medium, large, extra large in a variety of colors. Refer to size and color charts.