Three-fold sofa bed mechanism with sleeping surface in electrowelded mesh. High-resistance 25 mm diameter tube structure. Leverage is obtained by an extra thick belt. The structure is painted with fired epoxy powder. The Susy model can be matched with a polyurethane mattress. Maximum 180 cm in length and 7 cm in height for the electrowelded version. The Susy model can be attached directly to the frame at a height which goes from 4 cm to 8 cm from the ground.