Old world technology meets the 21st century. Wine Chillers were originally made before electricity and refrigeration. They were made of bisque ware (low fired and unglazed pottery like a typical flower pot).
Dunk bisque ware in a bucket of water and the water will soak into the pot. If you would place a wine bottle inside a water soaked wine chiller, the evaporation around the bottle would cool it slightly.
A plate was also needed to keep the water from dripping out onto your table.
Today, we glaze our wine chillers and fire them to stoneware temperatures. High fired glaze makes it safe to freeze the chiller (or just leave it in your freezer for ready use) and beautifies your chiller with bright colors.
Place your chilled wine bottle in your frozen wine chiller and it will stay chilled on your table without ice.
The picture represents the color category of Scarlet and Grey so the wine chiller will vary some in shape and coloration because they are individually glazed and made.