The Zonegrace tumblers are tough as well, and will keep your drinks as cold (or hot) as science allows. With 18/8 stainless steel construction, double-wall vacuum insulation, and No Sweat Design, they're perfect for the deer lease, cleaning table, or just the down time in between your outdoor exploring.<br><br> <b>Vacuum Insulation Technology</b><br><br> This tumbler has a double walled exterior with a vacuum between the walls. This means your drink has no medium for the heat or cold to transfer through. Your beverage will truly stay as hot or cold as long as possible. Even filled with ice or boiling water, the bottle will never sweat or get hot to the touch!<br><br> <b>Copper Coated Insulation</b><br><br> The exterior of the inner wall, in the vacuum sealed area, has been dipped in copper for added insulation. Copper reduces the transfer of temperature, adding even more insulation to your cup. This technology gives Simple Modern the best insulation of any tumbler on the market!<br><br> <b>18/8 Stainless Steel</b><br><br> The insulated tumblers are made of high quality food grade 18/8 stainless steel. Whether you are drinking water, beer or even coffee, this tumbler will not retain the taste or smell of any liquid. This reusable tumbler will help keep plastic cups and bottles out of our landfills.<br><br> <b>Durable Powder Coating</b><br><br> Enjoy the protection and color that rugged powder coating adds to the tumbler. Our powder coating is sleek and durable, making it the perfect travel companion. All of our colors have been hand selected according to the most popular fashion trends.<br><br> <b>Closing Flip Lid</b><br><br> This tumbler comes with a push-in closing flip lid. The tumblers come with two straws and the opening of the flip lid will fit most straws. The lid has a closing flip mechanism that helps mitigate the sloshing and splashing that comes with everyday life. This chemical free lid is dishwasher safe.