Collagen Casings take the place of using natural hog or sheep casings. These beef protein casings can be used for either fresh or smoked sausages. There is no preparation necessary; just put them on your stuffing tube and before you know it, you will have uniformly sized sausages. The19mm are snack stick size (remember, you will need a 1/2" O.D. tube or smaller for these). | LEM Collagen Edible Casings Clear Smoked 2 Pack | Size 19mm