The Never Ending Bottle!
I have two kids under 10 and they seemingly drink like horses! Days to the beach used to require 15 different bottle to ensure we didn't run out of the magical elixir of life but now we just have to take this beast! Happily does 4 refills and adding ice in makes sure you have some icy cold drinks all day long.
The shoulder sling also means you can carry hands-free or get one of the munchkins to carry something for once! Oh and the bright orange colour means it never gets lost.
Next stop, frozen margaritas for the school summer fayre!