Adding the TRIO Elevator (or heel lift) can help reduce the stress on the Achilles Tendon and relieve pain associated with Achilles Tendonitis and Sever’s Disease. When a structural short leg is present and Elevator can be applied. TRIO Elevators come in different heights and should be placed under the heel area of the orthotic. Choose between small, medium or large. They are manufactured from extra firm density to prevent wearing out or crushing.