I love the design of these cups and convenience / their innovative double walls (not to burn your fingers), to the point of having renewed my purchase with different sizes. Unfortunately after several months of use is the disappointment: it is specified that they go in the dishwasher, or they eventually crack, water is inserted between the two walls. The smallest shock is fatal to them, they are more fragile than glasses. Low resistance, which is not at the price paid or the brand reputation!