This waterbottle is made of food-grade silicone which is soft, drop resistant, lightweight and durable. This boys water bottles is BPA free. The cups for boys is odorless and free from any harsh chemicals which is important. This water bottles leakproof for school is very elastic, soft, non-slip, comfortable for holding with ergonomics design. Great for boys who drop bottles constantly.Flexible capacity - Shrink it to a handy tiny shape, or expand to the full 600ml. Size is perfect for both boys & adults. The travel water bottle is foldable which saves about 50% of space for outdoor activities. Easily squeeze. Very handy to carry around.