Joyjolt double walled  mugs are elegant and stylish. They are very light weight . You can hold mug for longer period without stressing your hands. Looks delicate but they are well sturdy. They keep my coffee/ tea  hot for some time but not for very long as I was expecting. Condensation does not appear on the Mugs which is a nice feature. They are Dishwasher, Microwave, Oven and Freezer Safe .I will recommend these to my family and friends .