304 GRADE, RUST-PROOF STAINLESS STEEL INSIDE- Made of the best quality, food-grade stainless steel our Hydra Trek water bottles are crafted to ensure the water inside retains a pure, clean taste with no chemical leaching. . COPPER COATED DOUBLE-WALL VACUUM INSULATION - The double wall vacuum insulation of the water bottle maintains the temperature of inside contents for hours and prevents condensation from forming on the bottles exterior. 20 HOURS HOT, 24 HOURS COLD- Keeps your drink cold for 24 hours or hot for 20 hours straight. Sip healthy with our BPA-free water bottles that are made with non-toxic materials. With our reusable water bottle, staying hydrated all day long just got easier. For the coldest drink, simply add ice cubes to your insulated bottle. EASY TO CARRY & USE, WIDE MOUTH -Pack your leak-proof, spill-proof and sweat-proof water bottle in your gym bag, travel backpack or purse. For your convenience, your stainless steel water bottle has a wide mouth that makes it extremely convenient to drink from. So whether you're outdoors or at your desk, our Hydra water bottles are the perfect hydration companion. FOR BEST RESULTS-For maximum effectiveness, before filling the flask with the beverage, precondition by filling hot water or cold water/ice. For optimal temperature maintenance, fill the bottle completely. Not advisable for carrying carbonated and alcoholic beverages. To avoid odour, keep the bottle uncovered when not in use. Clean with mild detergents only.