The Helios Fans SRSD 400/900 is a high-capacity circular duct silencer designed to provide effective noise reduction in ventilation systems. Positioned between the fan and the ventilated space, this unit significantly decreases sound transmission without restricting airflow.
Built with convenient spigots, it fits easily into standard 400 mm ducting and is ideal for larger HVAC installations. As part of a comprehensive range available in diameters from 100 mm to 400 mm, the SRSD 400/900 offers a longer attenuation chamber for enhanced noise suppression in high-demand environments.