Duralex Made In France Lys 4-Inch Stackable Clear Bowl, Set of 6 Lys 6 piece set includes 4 inch stackable clear bowls The original french tumbler, made by the company that invented tempered glass Duralex is 2-1/2 times more resistant to breakage, sudden thermal shock and chipping than normal glass 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