Blue thermos Frank Green Premium quality patented lid with button ceramic lining inside vacuum insulated 100% leak proof thermos BPA-free materials, FDA and EU approved Do not put in dishwasher or microwave Leak-free thermos in a chic metal design The coffee or tea thermos is made of premium materials and in an award-winning design. It will stand the test of time and the quality of coffee taste. Its walls contain vacuum insulation for better temperature retention. The interior is made of ceramic so as not to interfere with the original flavours of the coffee. Frank Green thermo flasks are eco-friendly, sensible, lightweight, colourful, practical, unbreakable and supremely stylish. They will never inadvertently leak coffee into your bag and are easy to operate even while walking with just one hand.