Heat-resistant glass and normal glasses are different! Unlike other glasses, heat-resistant glass uses material that contains strong heat resistant properties which could withstand sudden change in temperature. This has a difference in the manufacturing process as well. It also contains borosilicate which makes it capable of withstanding sudden change in temperature. Heat-resistant glass can withstand sudden change in temperature, thus it could be used not only in a refrigerator, a microwave and a dishwasher. LOCK&LOCK BOROSEAL uses heat-resistant glass for more safety.