Check the listing for details. VIVOSUN 4/6/8in Air Filtration Kit,Carbon Filter+Inline Fan+Ducting Speed Contro. Condition: New. Listed at 95.99 USD. About this item All-In-One Combo: 4/6/8in Inline fan combo enables your ventilation system set up in a grow tent, which is ideal for cooling down heat from lighting fixtures and controlling hot and humid conditions Premium Carbon Filter: Interior and exterior mesh construction provides 54% open area for free air flow; It is filled with 1200+ RC 412 Virgin Australian activated charcoal captures air contaminants effectively Multi-Layer Air Ducting: It comes with 3-layer construction--inner and outer layers are made of heavy-duty aluminum foil that is fire-retardant and its middle layer adopts PET thermoplastic 2 Rust-free Clamps: The kit includes a pair of clamps that are made of stainless steel, which are used for securing the connection between ducting and inline fan to keep the connected components in place Powerful Inline Fan: Made of galvanized steel，Equipped with an infinite speed controller, you can adjust the fan speed according to your needs, eliminate the air in the tent and achieve good ventilation effect: 4-inch inline fan runs at a speed of 2300 RPM and produces an air flow of 190 CFM, with a noise level of just 30 dB the maximum 6-inch inline fan runs at a speed of 2450 RPM and produces an air flow of 390 CFM, with a noise level of just 34dB the maximum 8-inch inline fan runs at a speed of 2450 RPM and produces an air flow of 720 CFM, with a noise level of just 38 dB the maximum