The Absolute Olympus Young Jump hind leg protector is specifically approved for young horses by the International Federation, but can be used on horses of all ages. Polyurethane and double-density EVA reinforcement is wider to provide maximum protection for the horse's fetlock.
NOT APPROVED by FEI for young horses (4-8 years) in Sweden,

Anatomically shaped, impact-resistant shell in polyurethane. Polyurethane and EVA reinforcement. Aerox, micro-perforated neoprene padding. 3D mesh. 5 cm double Velcro closure.