Build your own awesome backyard "rocket stove", which cooks food using only twigs and debris for fuel
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Ecozoom Rocket Stove - a sturdy little multi-fuel stove that's small enough to keep on hand for emergencies or take camping, durable enough be a primary cook stove.
Kelly Kettle Trekker Biomass Stove review. Boils water super fast using a handful of sticks! Love this stove!