This inexpensive flask works well if you need to keep water hot for up to eight hours, but come evening the coffee inside will have dropped to bathwater temperature. You can actually feel warmth radiating away right after filling it. After Four hours the water inside measured 79.9°C, after eight hours it was 66.7°C, and by the twelfth hour I measured a rather abysmal 47.8°C.
Still, for the price it's a very good flask.
Unfortunately we have run out of stock, for this particularobicred R37 item.