Wherever you go - bring goodies. No more need for disposable zip-lock bags or big and bulky packaging when on the go. With the storage compartments from Herobility, you get 100 ml/3.5 oz of leak-proof, freezer and microwave safe cans that you can bring anywhere. Theyre stackable. You can create an easy-to-carry-stack of Storage by locking several together. Attach one to the bottom of Herobilitys Baby Bottle, Sippy Cup, and Sport Bottle for a convenient storage solution. Use them for breast milk, formula powder, snacks, or whatever fits your need.