Duralex - Gigogne Clear Tumbler 220 ml (7 3/4 oz) Set Of 6 Set includes six 7 3/4 oz ounce glasses Duralex is 2-1/2 times more resistant to breakage and chipping than normal glass, can withstand sudden thermal shock. Can also withstand sudden thermal shock, from -4f to 212f Dualex glass is very hygienic, It is non-porous and does not absorb liquids, colors or flavors