Air treatment Sonata 4 – Low-profile air curtain for efficient indoor climate control. The Air treatment Sonata 4 is a compact and efficient air curtain designed for horizontal installation at the entrances of retail stores, restaurants, offices, and industrial buildings. With installation heights up to 3 meters, it ensures optimal air separation and protection against dust, fumes, and temperature loss. Suitable for environments with ambient temperatures from 0 °C to +40 °C and humidity up to 80%, this model features both AC and energy-efficient EC fans with airflow rates up to 4,800 m³/h. Its slim design, advanced Straw System for enhanced screening, and optional electric or LPHW heating make it a reliable choice for demanding applications.