SMBII Sports Medicine Boots provide 360 degrees of impact protection. Constructed from a 4-way stretch neoprene that conforms to your horse’s leg, SMBII’s provide support for the suspensory system and help prevent fetlock hyperextension. UltraShock lining absorbs shock from impact. SMBIIs have been proven to absorb and dissipate up to 26% of the negative energy from hoof to ground concussion. Exceptional value, solid in pairs.