An improved overreach boot for horse's lower legs is disclosed herein. In embodiments of the disclosed improved overreach boot, the boot has a shape that is winged by virtue of two concave indentations, such that when mounted to the leg of a horse, relatively little of the bottom surface of the boot comes into contact with the ground. This improves known boots, in which substantial portions of the lower surface contact the ground, causing the boot to pop-up or rotate. The disclosed improved overreach boot also advantageously relies on a lower protrusion to engage a cavity in a horse's hoof, which protrusion has a large, triangular cross-section to more securely engage with the horse's leg.
