BOROSILICATE GLASS MUG | Double walled glass tea mug

Unlike ordinary glass, borosilicate glass is prized for being lightweight and crystal clear to enjoy the color and clarity of your tea. Resistant to thermal shock, it is able to handle both hot and cold drinks without cracking. The double-walled glass construction insulates your tea. This glass tea mug with a handle is perfect for holding your hot tea while staying comfortable in your hands. Holds 12 oz of your favorite tea. How are double-walled glass mugs made? Borosilicate glass mugs start as a blend of glass materials melted and shaped into the mug’s elegant form.  Once the mug’s double walls are formed, a small hole that allowed air to release during the process is sealed with a tiny glass “plug”. This keeps the mug airtight and insulated. It’s a clever design detail—but it also means these mugs shouldn’t go in the dishwasher, since the plug seal can loosen over time with high heat or moisture. The air between the walls insulates the mug's contents keeping your beverage hot or col