The Helios Fans RSD 355/400 is a compact and efficient duct silencer engineered for use in ventilation systems where noise reduction is essential. Constructed from durable galvanized sheet steel, the silencer is internally lined with high-grade mineral wool to absorb sound effectively. The airflow side is protected with an abrasion-resistant fleece for enhanced durability.
Designed to match standard fan diameters (R 20), the silencer also includes pre-drilled mounting holes that conform to DIN 24155 specifications. With very low airflow resistance, the RSD 355/400 is an excellent choice for maintaining quiet and efficient air distribution in commercial or industrial HVAC installations.