This is a spring mattress with a "Box System" structure, characterised by small individually bagged springs. The special connection procedure guarantees noiselessness, cohesion and independence among the springs. Each individual spring towers as a result of an autonomous reaction to the pressure (piano keyboard effect); furthermore, the varying thickness of the steel thread makes it possible to obtain a structure offering 3 zones displaying a different capacity, thus ensuring a measured support to the different weights of different parts of the body. The resting surface is in WATERLILY®, an innovatory non-deformable and eco-friendly product, similar to natural sponge, displaying excellent quantities in terms of breathability, support and comfort.