Comfort Fleece™ Correction Pad System: 100% Merino Sheepskin allows for excellent circulation and provides superior padding for distribution of pressure points. The unique design allows you to design this pad with our memory foam inserts (4 pieces per pocket) or with 4 Impact Gel inserts (1 per pocket).Place Shim in one pocket or in all four, depending on the horse’s needs. Ideal for horses that are out of shape or returning from an injury. Fits saddles 16.5" to 18".