The Sure Grip Seat is designed to add security in the saddle with those hard running and quick turning horses, novice riders, young riders and those with physical challenges. The Magic Grip seat cover lies across the saddle seat from side to side with the straps over the back of the saddle and the fenders. Put the Leg straps over your pants on the ground, mount, and then fasten the leg straps to the seat cover. Seat and leg straps come together–order Extra Small, Small, Medium, Large or Extra Large. Size is determined by leg straps. To determine proper size, measure around upper thigh. All velcro straps, durable.