High Quality Content by WIKIPEDIA articles! A rocket stove/Rocket mass heater is a type of stove combining the air-intake with the fuel-feed slot in an opening terminated by the combustion chamber, further leading to a chimney and heat exchanger. A rocket stove is signified by ease of construction and simplicity of building materials while accepting small-diameter fuel such as twigs or small branches, yielding high combustion efficiency and directing the resultant heat onto a small area.