Home Hydro 0640 Mountain Air Filter, 150/1000 1130m3/hr Mountain Air Filters are a new range of filters which have been designed to give maximum quality, performance and durability It's simple functionality contains complex interior designs using the most unique materials. Mountain Air Filters require little maintenance and reduce noise levels considerably, ensuring an effective and efficient growing life cycle. They also offer superior airflow than normal filters due to the very low density but yet high mechanical strength of activated carbon used, which in turn gives better results and peace of mind.