This bottle uses the same principle as Brekveld’s Wine Cooler for Royal Tichelaar. The natural evaporation of water on the outside provides a cooling effect on the inside. The big difference with the cooler is the fact that the bottle does not have to be especially prepared. It only needs to be filled with water, after which the unglazed earthenware slowly absorbs the water and at the same time has a cooling effect. The silicone ring at the bottom has a twofold function. It ensures that the water does not leak through, while the rubberlike material provides a soft contact with the surface.