It has 400 independent springs individually coated with TNT (800 springs in double sizes). The springs are made of carbon phosphate steel wire. Thanks to the open cell structure of the memory foam and the springs that favour the passage of air, it can thermoregulate itself. Covered with hypoallergenic fabric, hypoallergenic padding, breathable 3D tape. Perimeter box in polyurethane foam. It is modelled both according to body heat and thanks to the applied pressure. The number of springs shown refers to the standard double size. It has the CE mark and the materials are certified. Completely made in Italy.