THIS 12OZ STAINLESS STEEL INSULATED COFFEE MUG IS MADE OF FOOD-GRADE 304 8/18 STAINLESS STEEL, LINER OF COFFEE MUG WILL NOT PRODUCE ANY TASTE AND WILL NOT RUST, AND THE STAINLESS STEEL MATERIAL IS DURABLE AND NOT EASY TO BREAK.WHEN YOU USE IT TO DRINK COLD BEER OR COFFEE AND OTHER BEVERAGES, IT CAN KEEP DRINKS AT THE OPTIMAL TEMPERATURE FOR HOURS ENSURING YOUR DRINKING. SUITABLE FOR VARIOUS OCCASIONS, CAN BE USED AT HOME, OFFICE, TRAVEL, CAMPING AND OTHER SCENES, AND ALSO ON VARIOUS HOLIDAYS SUC. 3.46" L X 3.46" W X 4.26" H