Double wall vacuum insulated stainless steel construction keeps your beverage cold for 24 hours and it can also keep your coffee or tea hot for six hours during backcountry ski missions in winter double wall stainless steel construction also means this bottle is naturally bpa free won39t leave a weird taste and prevents condensation on the outside on the bottle the rapid flow spout offers quick access to refreshing hydration and the cap conveniently stows in the handle so it stays out of the w