Bodum's insulated double walled glassware is made from durable Borosilicate glass. Borosilicate glass is very strong and heat-resistant glass that weighs less than traditional glassware. Used to make scientific lab glass, borosilicate glass (medical grade glass) is stronger than traditional "soda-lime" glass. Borosilicate glass substitutes boron oxide in place of the soda and lime used in most glassware. The boron oxide is like a glue holding the silicate together and due to the small size of boron particles, the glass is held together tighter, resulting in a stronger glass. The thermal properties are just as important to you the user. The glasses will not sweat in hot weather with a cold beverage inside. Just as important they will keep hot beverages warm and not burn your hand as you hold them.
More information about Bodum Double Wall Glassware Many people think the Bodum glass to be "thin" when they hold it. It is important to know the difference between borosilicate and soda lime glass. Borosilicate glass doesn't need to be as thick as regular glass to be as strong. Borosilicate is type of glass that is resistant to temperature and scratching. Borosilicate glass is dishwasher safe and will not become cloudy over time; even after 100 wash cycles, your Bodum glassware will be as clear as when you bought it. Treat your Bodum glassware it as you would any glass product and it will stand up to every day use for years to come. Dishwasher and microwave safe. Bodum insulated, double wall glass is handmade, so each glass may have slight differences in height, thickness & weight. These glasses will help to keep hot drinks warmer and cool drinks cooler.