Top positive review
154 people found this helpful
For those having trouble...
on April 9, 2010
For those of you having trouble with the cup's valve, before using the cup for the first time, remove the valve and squeeze each side of it (it's cut in a cross shape). This breaks the seal and allows the liquid to flow perfectly!
I absolutely love these cups, and since our first purchase of them, I can't bring myself to buy any others. They DO NOT leak, at all!