The Speedy Feeder Nursing Bottle features an adjustable valve which may be switched to three separate settings for the rate of milk flow. For a weak or premature calf, the slowest setting is desired. For stronger, older calves, the fastest speed saves time and energy.The Speedy Feeder’s special nipple, the Peach Teat, has a natural size, shape, feel, and features pump action--the natural squeezing of the calf’s jaw pumps milk through the teat.The bottle is large and well-designed with a handle which allows one-handed grip either forwards or backwards. The neck opening is a large 3" and has an easy-thread plastic cap. The bottle widens at the base for stability. Bottle capacity is 2.5 quarts.