It does not compress the withers, helps to prevent problems by distributing weight evenly. Anti-slip, shock absorbing hexagonal gel pad combined with micropile fabric and an inner 4 mm thick open cell foam is breathable, providing comfort to the horse’s back while maintaining contact with the saddle. Because of its hexagonal gel structure, air is compressed within the cells of this non-slip pad and is expelled as the horse moves creating a cushion under the saddle. Designed to fit under any style and size of English saddles. One size.