*LASER ENGRAVED - We use a professional, high end laser engraver to etch your design into a powder coated stainless steel tumbler. *Double-wall vacuum insulation with a clear lid *Narrower bottom to fit most standard cup holders. *It is 2X heat & cold resistant compared to a normal tumblers. *Powder coating. *Seamless construction so there is no leak point. *Hole on lid is big enough for a straw. *18/8 gauge Stainless Steel (18% chromium/8% nickel) - also known as Type 304 Food Grade. * Keeps ice cold for around 20-24 hours and liquids hot for around 8 hours.