Airontek’s Filter 125-400 is an activated carbon canister for odor control in indoor grow ventilation. It uses a 125 mm flange and a 400 mm body, fitting 125 mm ducting and common inline extractors. The model is rated for up to 450 m³/h airflow and is built as a closed-end cartridge with a flange on the opposite side for easy connection. Airontek recommends selecting a filter with capacity 20–30% higher than the extractor to improve contact time through the carbon bed. It is typically installed on the exhaust side to scrub outgoing air before discharge, helping to maintain cleaner recirculation and a discreet environment around the cultivation space.