Stacky Stacky has become a must-have for communities. The 16 cl Stacky glasses has a small size, designed to make it easier for children in school canteens or seniors to hold. The structure on the cup has two advantages. Firstly, the moulding hides the limescale deposits that can form during repeated washings. Secondly, the inner recess ensures that Stacky glasses can be stacked perfectly together. Made of tempered glass, Stacky is impact resistant.