The Universal Bag by Caldwell Shooting Supplies is constructed of high-quality leather and polyester. The leather gives you a secure rest and the polyester keeps the bag from stretching or sagging, allowing it to hold it's shape. This combination makes for the best shooting bag on the market. The Universal Bag has many uses. It can be used as a forearm or elbow rest; to raise the height of the rear bag; between the buttstock and the shoulder for heavy recoil long guns; as a heel rest for handgun shooting or even as a front rest.