Oasis Drink Bottles harness double wall vacuum insulation technology to significantly reduce heat transfer by conduction or convection. This technology prevents condensation from building on the exterior when storing cold drinks, and likewise, remains cool to touch when storing hot drinks.By using vacuum insulation technology, drinks remain cold for up to 24 hours or hot for up to 12 hours. Holds up to 500ml. Fits into a standard car cup holder. Easy to clean Double wall insulation keeping drinks cold for 24 hours or hot for 12 hours. Tight-fit twist cap with a BPA free Silicon Seal to ensure no leaks. Eco friendly. Made from high grade 18/8 stainless steel inside and out. The double wall, vacuum insulated body reduces condensation.