Essential Sippy CupThis sippy + training straw cup is designed to grow with your child from a sippy, to a straw, to an open cup, and it is the perfect transition cup from baby to toddler. The top lid reverses as a weighted suction base to add stability for straw training and reduces the chance of spills. As your child grows (or when using the sippy spout), you can flip the suction lid to a flat base. It can also be used to store our straw for on the go, keeping it clean