Bullfilter virgin coal filter from Australia. This coal is imported from Australia, extracted from deposits millions of years old. Triple action on odors! Better than recycled carbon, Hy-filterit is better than recycled charcoal, it filters perfectly the odors of your indoor room. Perfect for hydroponics and indoor growing, Bullfilter the new charcoal filters will revolutionize your indoor garden. Absorption capacity RC-4/8 to cover a maximum area of 1000m2. More info in the press review Bull filter or on the supplier website bullfilter.com.