eddy-turn, ive done jerkey cooks as low as 140 without doing much except using small pieces of spent lump and just a small amount. any lower and you need a second box connected to the top vent with a dryer vent hose, or a second egg for the fire with its exhaust hooked to the lower vent of the other egg, or a big pan of ice under the food which ive seen done for smoking cheese. someone here probably has the pics of those here