Duralex is 2;5 times more resistant to breakage and chipping than normal glass, can also withstand sudden thermal shock: from -4°f to 266°f Shock resistant tempered glass can go straight from the freezer to the microwave Duralex glass is very hygienic; it is non-porous and does not absorb liquids, colors or flavor; Lead free, cadmium free, and BPA free Set includes 6, 3;5 Inch Stackable Bowls Freezer, microwave and dishwasher safe; Made in France