KEN BROWN 20 Inch High Velocity Box Fan Review: Up to 4700 CFM
KEN BROWN's 20 inch metal box fan moves up to 4700 CFM on high, runs below 60dB, tilts through 360 degrees and has galvanized steel construction.
By Daniel Brooks
Updated October 28, 2026
The KEN BROWN 20 Inch High Velocity Box Fan is a heavy-duty metal box fan that moves up to 4700 CFM on high, runs below 60dB and tilts through 360 degrees. For more models, see our Box Fans page.
Our Verdict
This is the most powerful box fan on our lists by rated airflow. A galvanized steel housing, aluminum blades and a sealed dual ball bearing motor make it a genuine shop fan.
It is bulkier and louder than a home box fan, so it belongs in a garage, workshop or gym rather than a bedroom.
KEN BROWN 20 Inch High Velocity Box Fan
As an Amazon Associate we earn from qualifying purchases. Product prices and availability are accurate as of the date/time indicated.
Key Specifications
| Feature | Specification |
|---|---|
| Brand | KEN BROWN |
| Model | 20 inch high velocity |
| Size | 20 inch |
| Airflow | Up to 4700 CFM |
| Noise | Below 60dB |
| Tilt | 360 degrees |
| Housing | Galvanized steel |
| Blades | Aluminum |
| Safety | ETL, thermal overload protection |
Design
The housing is galvanized steel with a rust-proof powder coating, and the blades are solid aluminum. It measures 10.16 x 22.83 x 24.21 inches.
The head tilts through 360 degrees to aim air across the floor or up at the ceiling, and a top handle and nonskid feet make it easy to move and place.
Controls
A rotary switch picks low, medium or high, and KEN BROWN says noise stays below 60dB even at full speed.
Safety features include ETL certification, thermal overload protection and a 3-prong plug with fuse.
Placement Tips
Stand the fan where it can push air across the room toward where you sit or sleep, rather than into a wall or corner. Keep it on a flat, stable surface, and keep the cord out of walkways.
On cool evenings, a box fan facing into the room from an open window pulls in fresh air, and a second fan facing out of a window on the other side of the house pushes warm air out to create a cross breeze.
Running Costs and Care
Box fans use far less power than an air conditioner, so running one all night costs very little. Pairing it with your AC lets you raise the thermostat a little and stay comfortable.
Unplug the fan and wipe dust from the grilles and blades every few weeks during heavy use, since dust cuts airflow and adds noise. Store it clean and dry over winter, ideally in its box or a bag.
How It Compares
Against the MAN 20 Inch High Velocity Box Fan, the KEN BROWN lists more airflow and an all-metal build, while the MAN is lighter with a polypropylene housing.
Against the Xcity 18 Inch Metal Box Fan, the KEN BROWN is a larger 20 inch fan with higher listed airflow, while the Xcity costs less.
Pros and Cons
| Pros | Cons |
|---|---|
| Up to 4700 CFM | Bulky |
| Galvanized steel | Louder than home fans |
| Aluminum blades | Overkill for small rooms |
| 360 degree tilt | No timer |
| Thermal overload protection | Industrial look |
Who Should Buy It
| Who Should Buy It? | Who Should Look Elsewhere? |
|---|---|
| Garages | Bedrooms |
| Workshops | Small rooms |
| Gyms | Window use |
| Warehouses | Quiet spaces |
For more options, see our picks for the best high velocity box fans and the best box fans for garages.
Final Verdict
The KEN BROWN 20 Inch High Velocity Box Fan is a powerful, all-metal box fan for garages, shops and big spaces. You can check the current price and details for the KEN BROWN 20 Inch High Velocity Box Fan.
Frequently Asked Questions
What is the CFM of the KEN BROWN box fan?
Up to 4700 CFM on high speed.
How loud is it?
KEN BROWN says it runs below 60dB at full speed.
Does it tilt?
Yes, through 360 degrees.
What is it made of?
Galvanized steel with aluminum blades.
Is it ETL certified?
Yes.
About the author
Daniel Brooks is a home cooling editor at WikiCooling, covering window, portable, through-the-wall and mini-split air conditioners, fans, and dehumidifiers. He researches cooling capacity, energy efficiency, noise levels, installation requirements, and buyer feedback to help homeowners choose the right unit for their room size, climate, and budget.