Because these tumblers are made of tempered glass, they're shock- and chip-resistant and ideal for both hot and cold beverages; they can also go from microwave to table to freezer to dishwasher with ease, and they're stackable for compact storage. Made in France.After inventing the glass-tempering process in 1939, Duralex has spent the decades since making stylish, functional, and durable tempered glassware and tabletop pieces in La Chapelle-Saint-Mesmin, France. Much like its process, the quality of its glassware has remained unchanged over the years, and these traditions have helped the company become a familiar name in households around the world.