This kettle goes under different names, eco-kettle, thermete, volcano kettle but whatever the name it is a terrific piece of gear. Inside is a cone with the largest diameter at the bottom narrowing to the chimney at the top. You take the lid off and put water into the outside funnel. Gather a bit of dry grass and leaves, light it and put the kettle on top. Then feed a few sticks down the funnel. In no time at all it has boiled. There is almost no fire to put out and with a bit of dirt scuffed over it you cannot see that a billy has been boiled. We use it all the time for a cuppa on the track. Of course when camped and the camp fire burning we use an ordinary billy.