Size: 140mm (important—bigger = quieter airflow)

* PWM (4-pin): Auto speed control (major selling point)

* S-FLOW blades: Marketing for high airflow

* Low noise: “Super Silent”

* Anti-vibration mounts

* Airflow boost claim: +30%

👉 Translation for buyers:

* Good for gaming PCs

* Quiet cooling upgrade

* Better than cheap stock fans

Akasa Viper 140mm PWM case fan featuring S-Flow blade design for improved airflow and quiet operation. Ideal for gaming PCs or upgrading system cooling. Includes anti-vibration mounts and 4-pin PWM connector for automatic speed control. Brand new in original packaging.” Buyer beware no guarantees no warranty is being provided. Please view conditions of the item and may determinations, we do not guarantee anything other than what you see in our pictures. Seller does not accept returns.