Duralex Set of 6 Wave Tumblers, Clear, 9.5-Oz. These contemporary glasses feature organic waves, lending them a modern aesthetic that is perfect for both entertaining and everyday use Constructed in France of impact- and chip-resistant tempered glass by Duralex, the company that invented the glass tempering process Tempered glass is nonporous, so it wont absorb liquid and is two-and-a-half times stronger than ordinary glass Duralex glasses are stackable and safeif broken they shatter into small chunks as opposed to jagged shards, reducing risk of injury Microwave, freezer and dishwasher safe