Perfect tool for nursing baby pets that require bottle feeding. Comes with capacity markings on the side to ensure accurate measurements of fluid. The cap features textured edges for an easy grip. The nipples are not pre-punched so you can cut them and adjust the flow rate yourself. BPA-free and made in the USA with quality plastic. 2 Ounce: Has smaller nipples, recommended for puppies, kittens, guinea pigs, ferrets, rabbits, raccoons, squirrels, or other small animals. 4 Ounce: Has larger nipples, recommended for large puppies, monkeys, piglets and other large babies.