Our engineers reduced the weight, and increased the power and convenience for you! Sore in the back from stiffness, arthritic conditions or hard work? Ligament, tendon, muscle or bone injury? Fractures, poor circulation or tie up? This is the newest system in use by our U.S.Equestrian Team. The Sentry system is used here by Eros, who won Olympic medals with Anne Kursinski. Ask us about rental options.