The PRO H35 Splint boot is the perfect low profile protection for the splint bone and cannon bone when no previous injuries have occurred. Easy to apply, the matched hook and loop fasteners make for a very durable protective wrap. The body is constructed of orthopedic grade neoprene with a shock absorbing pad sewn between the body and the outer sheath. Machine washable. Boot Sizing: Measure around leg halfway between the knee and fetlock: Under 7" = Small 7" to 8" = Medium