This 30 oz black stainless steel polar camel travel mug feature double-wall vacuum insulation. The mug has a narrower bottom to fit most standard cup holders. It is 2X heat & cold resistant compared to a normal tumblers. It is ready to be customized with your favorite logo,phrase,photo. It engraves to silver. You can also add an additional design for $4 more to make it extra special. They make great gifts or promotional items. It is NOT recommended for dishwasher use. Prolonged dishwasher use will break down the materials used to keep your beverages hot and/or cold for hours.