Duralex was founded in 1929 and they have been making their glassware and tabletop items in La Chapelle–Saint–Mesmin, a city in France. Since 1939, Duralex invented the glass tempering process, the name Duralex has been associated with resilient glassware, thanks to their proprietary tempering process. The original tempered (toughened) Picardie glasses are still in production in France and are known as the "Original French Tumblers. Duralex has reached a level of excellence that makes its products recognized throughout the world. Duralex is and will always remain a true French manufacturer of glassware and tabletop products and is the only glass manufacturer that makes 100% of their products in France. Duralex is 2–1/2 times more resistant to breakage and chipping than normal glass. It can also withstand sudden thermal shock from –4°F to 212°F. Duralex glass is very hygienic: It is non–porous and does not absorb liquids, colors or flavors. Dishwasher, fridge and microwave safe. Products maintain the original look for years. 10 pc bowl set includes: 10 nesting bowls: 1 ounce, 2 ounce, 4 ounce, 6 ounce, 10 ounce, 1/2 quart, 1 quart, 1– 1/2 quart, 2–1/2 quart, and 3 1/2 qt bowl.