The MAM Thermal Bag is made of high-quality material and the insulating layer inside keeps hot water hot or cold formula/breast milk cool for up to four (4) hours. The bag is easy to use and very convenient when you are out and about or travelling. The thermal bag has a handy Velcro leash or hook so it can be attached to changing bags and pushchairs. The MAM Thermal Bag for Feeding Bottles is designed to keep water hot and cold formula or breast milk cool for up to four hours. This easy to use bag holds a single 160ml or 260ml bottle and is perfect for when you’re on the go. It clips easily onto a pushchair or changing bag and comes with a Velcro leash. Wipe with a damp cloth after use and remove milk spills instantly. Ideal for travelling.