Features a unique three-piece stacking design with a specialized vent system for wood gasification and multi-stage combustion (first, second, and third combustions). Burns both wood and wood gas for cleaner, more efficient fire and better fuel use. Leaves fine white ash, indicating complete combustion. Includes a durable nylon stuff sack for easy storage. Nests inside TOAKS 1100ml or 1600ml pots; can also contain TOAKS 375ml or 450ml cups within the set. Promotes efficient pyrolysis of wood, maximizing heat and minimizing smoke. Usage Tips: Pack vertically-oriented sticks to optimize space and airflow Keep wood below top side holes of the internal cylinder to ensure proper air mixing and secondary combustion Add additional wood through the top small window if needed, but minimize interruptions during burning