LEAK PROOF - Smart two-piece valve prevents messy spills (even if they shake or flip the cup) SOFT STRAW - The straw is made from soft silicone which is gentle on small mouths but still durable and bite resistant DOUBLE WALL INSULATED - This sports water bottle helps keep their ...LEAK PROOF - Smart two-piece valve prevents messy spills (even if they shake or flip the cup) SOFT STRAW - The straw is made from soft silicone which is gentle on small mouths but still durable and bite resistant DOUBLE WALL INSULATED - This sports water bottle helps keep their drinks cool while they play, learn and explore FOLDING LID - Our tumblers are designed with a convenient lid that flips between sips, to help keep straw clean EASY TO CLEAN - All parts are dishwasher safe and BPA free