This bottle is what we use here with our new babies. These tiny bottles are perfect to keep with you with water/apple juice on trips to keep your monkey hydrated. Just use a little pressure to help babies nurse. My monkeys get excited when they see the bottle no matter how old they are. Holds about Â½ ounce of formula for your baby. Comes in 1/2 ounce and 1 ounce size. Add the special nipple and you're set to go!