This is an expandable medium to large hookah vase gasket. Due to the inconsistency of glasses in the hookah industry, it has always been difficult to find the right vase gasket to fit a hookah. These gaskets have helped solve that problem. They stack on top of each other to create an air tight seal so that you can custom fit them for your particular hookah. They will not work to replace gaskets for small hookahs that use size 22 gaskets. We recommend stacking three for a medium size hookah (replacing a size 26 to 28 vase gasket) and four for a large size hookah (replacing a size 30 to 32 vase gasket).