Our sleek and slender 16-ounce glass tumblers are made from the same material as lab glass (borosilicate glass). This means they’re not only great for iced and cold drinks, but they won’t crack or budge under the pressure of high-temperature beverages. Our glass tumblers are elegant yet understated and compliment any occasion that calls for something sippable. What’s in it: Borosilicate glass. What’s not in it: Lead, seams, and plastics of any kind. It’s all good: This product is oven safe, dishwasher safe, microwave safe, and heat resistant. Made in China.