Recharge with a heartful cup of coffee, this double double friendship glass is mouth blown and can be used for cold or warm beverages. Its unique design is appealing to the eye when filled with your favorite beverage. With its double layer of borosilicate glass it appears as though the liquid is 'floating' within the glass. The double wall creates a thermal effect, helping to keep your cold drinks cold and your hot drinks hot for longer periods of time. These mouth blown glasses are an exciting product for any home, restaurant and cafe and they are a definite conversation piece. Please Note: Because the glasses are mouth blown, each one may have slight variations in height, thickness, and weight. We recommend using care when placing ice into the glass to avoid fracturing the inner layer. Do not use metal spoons or place the glass into a crowded dishwasher