Voted North America’s Best Filter – FIVE TIMES!! (3 Year Life) MountainAir® Filters are a new range of filters that have been designed to maximum quality, performance and durability. No other filter has been able to last more than 3 years duration with constant use. It’s simple functionality contains a complex interior design using the most unique materials available. MountainAir® Filters require little maintenance and reduce noise level considerably ensuring an effective and efficient growing life cycle. They also offer more superior airflow than normal filters, due to the very low density but high mechanical strength of ‘Activated’ carbon used.