The bottle is molded from a sturdy plastic that withstands repeated use and can be sanitized between feedings. A soft, flexible silicone nipple fits the top of the bottle and is shaped to simulate the motion of a mother's nipple, encouraging a natural suckling action that helps develop facial muscles and stimulates normal saliva flow. Graduated markings run along the side of the bottle so a caregiver can monitor how much liquid an animal has taken at each feeding and help avoid over- or underfeeding. The nipple ships without a pre-cut opening, so a small hole is typically made with a razor blade or a fine needle before the first feeding, which allows the flow of formula to be adjusted to the animal's needs. Each pack contains six complete bottles, suited to households or facilities feeding more than one animal or rotating nipples between cleanings. Bottles and nipples can be washed with a bottle brush and sterilized with boiling water for repeated use.