Thanks to the great quantity of additional refractory material (70 kg optional kit), the Plus version of X range guarantees many hours of pleasant heat even after the flame is extinguished. In the system three special heat accumulation rings have to be installed right above the combustion chamber of the wood-burning stove and made in Durasic®. This extraordinary and innovative material is made up of silicon carbide and special refractory clays highly resistant to thermal and mechanical shocks. The combination of the two elements exclusively of natural origin, creates a highly performant mixture, with no equivalent on the current accumulation stove market. The result is great heat accumulation reached quickly and that will be slowly and gradually released into the room. This release will be even longer in the X Rock model covered with 116 kg of Serpentine stone.