This cup can sit in the hot Miami sun or in our stroller at Disney for hours at a time and STILL keep the ice cold water. I recommend 1,000 times over and over, i've been through TONS of sippie cups and water bottles this is undoubtedly the BEST! I have the 28oz pink, my husband uses the black andI got the 16 oz Mickey version for our son. Perfect for long days at the park or beach. You won't be sorry.