MiiR Tumbler is a modern cup made of stainless steel, with double walls and 350ml capacity. Sturdy, yet elegant, and keeps temperature of the beverage longer than traditional mugs. Perfect for home, office or on the go. Thermo 3D™ Double wall vacuum insulation technology keeps the temperature of the beverage - hot or cold. The walls are made of 18/8 medical grade stainless steel. The material does not transfer flavour and does not add metal aftertaste. Hand wash recommended, however, the cup is top-rack dishwasher safe.