Acoustic Ducting Size:4" it's built around Omega's two

it's built around Omega's two ceramic tube technology

or smaller to larger

Material: Durable rigid plastic or aluminium (standard reducer construction)

If you need to knock down an existing pest problem fast

Vortex Acoustic Ducting - Insulated Ducting That Cuts Fan Noise

Acoustic Ducting Size:4" it's built around Omega's twoVortex Acoustic Ducting Insulated Ducting That Cuts Fan Noise Best for: growers running an inline extraction fan who need to quieten the system down without fitting a separate silencer box. Our thoughts If your grow room shares a wall with somewhere you actually sleep or live, standard ducting on a decent sized fan gets old fast. This swaps the noise problem out for a quieter hum without adding another box to your extraction line. It won't make a loud