Tapered Aluminum Heel Riser Is 1 1/2'' Tall x 4 1/2" Wide. Mounts under the throttle pedal for improved leverage and comfort. Heel riser has a non-skid top surface. Using a heel riser in your cockpit will keep your feet at the correct angle over the duration of the race, which will result in less fatigue in your legs and calves. Triple X Outlaw Tip: Fatigue plays a major factor in winning and losing races, especially early in the season. Triple X Heel Risers help combat fatigue in your legs and calves by positioning your heel above the pedal, which will keep your lower body fresh for those times where you need optimal brake and throttle control.