CoastLine Double Wall Insulated Glass Espresso & Shot Glass Set | Pair of Illusion Floating Liquid Drinkware for Coffee or Alcohol | Hand Blown for Hot or Cold Beverages DOUBLE WALL BOROSILICATE GLASS: (2.0 oz) is naturally BPA, toxin and lead free; borosilicate glass will not impact the flavors of the contents. TEMPERATURE CONTROL: Keeps drinks hot or cold; double wall glass prevents heat or cold transfer and does not sweat when filled with cold beverages or desserts. DOUBLES AS SHOT GLASS: Perfect size to use as a shot glass and for spirits served neat or with a cube of ice such as whiskey, bourbon or scotch. DISHAWASHER SAFE: Your double wall espresso glasses will not become cloudy over time - even after 1,000 dishwasher cycles! OPTICAL ILLUSION EFFECT: contents appear to be floating! A perfect gift for the person that entertains or enjoys unique glassware.