Model of a double baker's oven, made by master mason Elfström. Described in the Norberg's inventory of 1779 as "Model of a double baker's oven, by the master mason Elfström, made in a way that one oven is above the other, an another below them, which is fireplace, whose heat passes below, over, and inbetween the both upper ovens, in which the bread is baked in, without fire or ash can come to them, wherefore also in them ceaselessly can be baked.". The model is numbered "D.6.e.4.".