A stainless steel mug with a "seamless sen" that combines the seal and seal together. Even after 6 hours of boiling water at 95 degrees Celsius/4 degrees Celsius cold water is under 9 degrees Celsius even after 6 hours. The inner surface is fluorine coated, so it won't leave stains or coffee stains. Along with your favourite accessories. Easily fits into small bags. Easy to use and carry, this mug is recommended for a variety of occasions, including the office and going out.