After the development of tempered glass in 1939, Duralex has been making glass in France for more than 80 years and is the only glass manufacturer that insists that 100% of its products are produced in France. Duralex's tempered glass has a glass strength of 2.5 times that of a typical glass. In addition to its toughness and durability, it has amazing heat and impact resistance. When it is damaged, it will break into numerous obtuse angle particles to reduce damage. They can be stacked for easy storage and space saving for microwave ovens, refrigerators and dishwashers. In addition, the non-porous nature of the tempered glass makes the Duralex glass easy to clean, free of odors and stains, and maintains a new look after many years of use.