Swiss Glass Double Walled Mugs. Packed in sets of 2 and available in either 350ML or 450ML sizes CAPACITY - Set of 2 X 350ML or 2 X 450 ML these glasses are perfect for a coffee shop style latte, cappuccino, tea or your favorite hot beverage. KEEPS YOUR DRINK HOT FOR LONGER - Double-walled swiss glass, hand blown glass insulation keeps your coffee hot for longer and is cool to touch as there's air in between the two layers of glass which keeps the rink hot and the outside cool. DURABLE BUILT TO LAST - Double insulated wall technology with compressed air shield makes these glasses extremely sturdy and durable. DISHWASHER AND MICROWAVE SAFE- Double-walled swiss mugs are dishwasher and microwave safe. LFGB certified food grade glass is non-toxic, BPA-free, heat-resistant. Whether.