16 oz: The Willow Breast Milk Cooler holds up to 16 ounces of breastmilk with the ice pack & 27 ounces without. (That's 3-4 pumping sessions' worth of milk on average.)

25 oz: The Willow Breast Milk Cooler holds up to 25 ounces of breastmilk with cooling & 37 ounces without cooling. (That's 5–6 pumping sessions' worth of milk on average.)

You can put the stainless steel Cooler Bottle, Lid, Cooling Cup, and Cooling Cup Spout into the dishwasher. We recommend hand-washing the Ice Pack.

For optimal results, put the Ice Pack in the freezer for at least 8 hours, and ideally up to 12 hours.

According to the CDC and ABM guidelines, breast milk can stay in a cooler with ice packs below 59°F for up to 24 hours and remain at a safe temperature.

The 16 oz. Cooler is 9.75’’ tall and 3.75’’ wide at the widest point. It fits in most standard cup holders.

The 25 oz. Cooler is 10.5’’ tall and 3.75’’ wide at the widest point. It fits in most standard cup holders.

Yes! TSA regulations state that any medical necessary gel ice packs are exempt from liquid travel restrictions in any state (eg. melted, slushy), and with or without the presence of breast milk.

Our Breast Milk Cooler was designed and tested specifically for breast milk storage. For more information on storing formula, refer to the Centers for Disease Control (CDC) guidelines for safe milk storage.

Yes, the formula is designed to store milk from multiple pumping sessions. Only combine milk pumped over the same 24 hour period.

Milk should only remain in the Cooler for 24 hours before being transferred into a breast milk storage bag and kept in the refrigerator (for up to 4 days) or freezer (for up to 6 months).The Cooler should only be stored in the refrigerator with the frozen ice pack in place.

Yes, this is a great option if you are concerned with mixing freshly pumped & already cooled milk.

Rest assured, we have tested our cooler with ice cubes (even adding multiple batches of warm milk!). When you add fresh breast milk, the ice will begin to melt as it cools down your milk. Once your milk is cooled, the vacuum insulated bottle will do its job! If you’re still concerned, you can always check the temperature of your milk and add more ice to the cooling cup.