Made of durable borosilicate glass, the Kvadrant drinkware line has long been a staple of the Bodum assortment. Borosilicate glass is an excellent material for everyday use because of its durability; not only is borosilicate heat safe, it will never cloud in the dishwasher. The 17 ounce cooler is great for any beverage, hot or cold. Kvadrant drinkware is stackable and comes in a set of 6. Kvadrant is comfortable to hold due to its shape and the fact that it isn't as heavy as traditional soda lime glass due to the lighter weight of borosilicate glass.