SIMPLE Boot is the Multi-Purpose Hoof Boot, excellent for protecting your horse"s hooves on hard, rough terrain. The ultimate protection for the barefoot horse. Great for comfort for chronic pain and hoof sensitivity; rehabilitation from injuries, abscesses, navicular disease, laminitis/founder, punctures, sole bruising and contracted heels. Can be used for protection during trailering and breeding or taken on the trail as a "spare tire" for lost shoes. Size 4 fits a hoof that is 5 1/4" - 5 1/2" in length. Sold in pairs.