What the Air Box 1 Stealth Edition Is Rated To Move
Airflow figures on box filters get quoted loosely, so start with the manufacturer numbers. Maximum is 400 CFM, recommended is 200 CFM, and minimum useful airflow is 75 CFM, at 1.8 inches water gauge when it is worked flat out. Inlet and outlet are 4 in, the unit measures 20.25 x 8 x 12.25 in and weighs 18 lbs. Inside is one replaceable cartridge of 12 x 20 x 1 in activated charcoal. Maximum operating temperature is 176 F. The recommended figure is the one to design around, because contact time is what removes odour and pushing to maximum shortens it.
Where a 4 Inch Inline Carbon Filter Sits in a Duct Run
A 4 inch inline carbon filter in this format hangs flat rather than as a cylinder, which changes what fits where. The rectangular body tucks against a ceiling or sits above a fixture, and it hangs from rope, chain or ratchets through its own mounting points. Airtight construction means it works on the pull side or the push side, so it can scrub exhaust or clean intake. When the cartridge is spent, it slides out and the housing stays exactly where it is. That is the whole case for a box filter over a throwaway cylinder. The trade is bulk: this is a boxy shape in a small tent, and a cylindrical filter of the same rating takes less headroom.
Key Features
- 400 CFM maximum rating: With 200 CFM recommended, which is the figure to size a fan around.
- Four inch flanges: Matches standard 4 in ducting on both the inlet and the outlet.
- Single replaceable cartridge: A 12 x 20 x 1 in charcoal element that slides out with the unit still hung.
- 18 lb steel housing: Outlives the media, so long term cost is cartridges rather than whole filters.
- Push or pull: Airtight construction lets it scrub an exhaust run or clean an intake run.
- 176 F maximum operating temperature: A stated ceiling, which matters in a sealed room running lights hot.
Technical Specifications
| Specification | Value |
|---|---|
| Brand | Air Box |
| Model | Air Box 1, Stealth Edition |
| Part Number | HT4496 |
| Maximum Airflow | 400 CFM |
| Recommended Airflow | 200 CFM |
| Minimum Airflow | 75 CFM |
| Pressure Drop | 1.8 in water gauge at maximum airflow |
| Inlet and Outlet | 4 in flanges |
| Unit Size | 20.25 x 8 x 12.25 in |
| Weight | 18 lbs |
| Cartridges | 1 |
| Cartridge Size | 12 x 20 x 1 in |
| Media | 100% activated charcoal, premium virgin coconut |
| Max Operating Temperature | 176 F |
| Returns | 14 days from delivery if unused, with a 30% restocking fee and return shipping paid by the customer, per the Air Box manufacturer policy |