All fresh USA rawhide has a thin layer of collagen on one side. This provides the intense flavor that Wholesome Hide is famous for. For the inside-out product, we choose hide that has a particularly thick layer of collagen and roll and dry the product with the collage layer facing out. This gives dogs who are “passive chewers” the instant gratification they need to get the teeth cleaning and soothing properties rawhide that makes rawhide so good for dogs.