Pro Choice Comfort-Fit SMx ½" Air Ride Saddle Pad - Limelight, These close contact Comfort-Fit pads feature a ½" breathable SMx Air Ride core. Developed from the horse’s back up, the Comfort-Fit SMx Air Ride Saddle Pad is contoured to follow the curve of the horse’s spine. As a result, this pad locks in place allowing full movement. The SMx Air Ride core is made of a unique material that absorbs shock while allowing air flow through a natural cooling system.