Modular sofa provided with a metal adjustable back mechanism. The back cushion is filled with polyurethane foam and a layer of acrylic fibers. The wooden frame is supported by intertwined elastic belts. The seat cushions are filled with polyurethane foam that is covered with anti-allergy goose feathers. The backrest pillows are filled with anti-allergy goose feathers. The base is available in chrome-plated or black metal.