Insulation type: Double wall Food safe Stainless Steel. Unique DTP Coating: The bottles come with new and advanced DTP Coating that is resitant to fading, scratching or peeling over time, A range of colours and an elevated matt finish improves the overall look of the bottles. Vacusteel Technology comes with double stainless wall with Copper coating on the inside to minimize loss of temperature and keep beverages hot or cold for a prolonged period of time. Compact design perfectly suited for an outdoorsy lifestyle like Hikes, Treks, Camping, Sports, Gym and other adventures. Store it in your bag with ease. Pre-condition bottle with hot water if using for hot beverage and cold water if using for cold. The 304 stainless steel also ensures hygienic conditions to store beverages and is resitant to oxidation or mal odours; BPA and phthalate free, all plastic parts are food grade non leaching and toxin free.