GAS Carbon filters comprise activated carbon, which cleans and de-odorizes air passing through the unit. It traps impurities and unwanted odours on the surface. Phresh filters fit onto ducting and stop pests and pollen from entering your grow environment. RAM's carbon filters are designed for air treatment. They're durable, resistant, and have an extensive lifespan. MountainAir's units use absorption technology and activated carbon to ensure an odourless climate. If you're looking to create optimum climate conditions in your grow room, check out the carbon filter products available at London Grow.