These stackable snack cups are great for all ages and can hold anything from baby formula, and toddler snacks, to pet treats or just about any other treat that can be taken on-the-go! The versatile Snack Stack system can expand to your children's needs. It's the perfect companion for errands, day trips or even the blanket fort that's permanently set up in your living room. All Re-Play snack stacks are made from recycled milk jugs (HDPE recycled plastic) and are available in a wide variety of colors.