The Avent Thermabag is perfect for day trips with baby or just when you are out and about. You can store cold expressed milk/formula or pre-boiled water for up to 4 hours. The Thermabag has a wide adjustable shoulder strap for optimum carrying comfort. Designed to fit all AVent bottles, VIA and Magic CupsEnsures bottles stay warm or cool Sleek, slim and versatile design Adjustable shoulder strap Designed to hold Avent Bottles, VIA & Magic Cups