This Hilason Western Grip Seat is designed to add security and balance in the saddle for those hard running and quick turning horses novice riders and young riders . It stops slipping and sliding when on the run and in turns. It attaches to saddle and around thigh with Hook and Loop fastner straps and fits most barrel saddles.SIZE DETAILS BASED ON THIGH MEASUREMENT :XS SMALL : 11 inch to 16 inch.SMALL : 12 inch to 17 inch.MEDIUM : 14 inch to 21 inch.LARGE : 19 inch to 25 inch.X LARGE : 23 inch to 32 inch.