We added extra insulation for maximum performance. Featuring our Trimax triple insulation technology, the Eco Vessel Boulder water bottle has been tested to keep water cold for more than 36 hours and retain heat for about 12 hours. Perfect for water, tea, coffee, soup or just about any drink. Its tight screw on top will keep your drink securely inside, where it belongs. It has a wide mouth to easily accommodate ice cubes and a convenient drinking spout. The Boulder features a removable tea strainer/ice dam. It's made of #304 stainless steel and is free of BPA and phthalates. The Boulder is a sturdy, high quality, stylish bottle for the office, tennis courts, golf course, on the trails... anyplace, anytime. 100% recyclable.