This vaccum beverage cup is made of 304 heat resistant stainless steel surrounding its interior and 201 stainless steel and both components function to keep contents (either hot or cold) in perfect condition for longer periods of time by diallowing the movement of air in the mug. This beverage holder conveniently holds about 354mL of fluid. It should be hand-washed only and is not compliant to use in microwaves and freezers. Its excellent matte color shade gives that cool feel during its usage.