The material of our product is high borosilicate glass and the advantage for our glassware is as follows: 1.Non-porous pyrex glass. It won't absorb food odors, flavor or stains2.Higher resistance to mechanical shock, scrach resistant3.Heat resistant, tolerance 300 degree no break or fissure4.safe for microwave, oven, diahwasher, freezer, refrigeratory, etc.4.Superior quality and competitive price5.Sharp dowm temperature tolerance: heat for 10 min and use temperature water with sharp down temperature at 130 degree, no break or fissure on the product6.Sharp rise temperture tolerance: hold in freezer at -16 _-18 degree for 30 min, then with high temterture cotton put into oven at 200degree, no break or fissure.About our prodect Our main product is pyrex glassware, such as: glass bakeware, glass casserole, glasscontainer, storage set, glass ovenware, microwave glassware and other heat resistant glassware If you are interested in our products,don't hesitate to contactus. Waiting for your cooperation.Thanks.