PC Fan - size: 40 × 20mm, 5000 RPM, 5 V, maximum noise level of up to 14,9 dB, 3pin This Noctua NF-A4x20 5V represents a very effective PC fan that has been designed specifically to regulate the air circulation of your computer. The fan will suit those who do not want to be disturbed by a strong backlight in the night hours, since this fan has no backlight. Another advantage is the the lower cost of the fan. The 40 mm fan size makes it easy to connect with all popular PC case formats. Also consider the operating voltage, which for this model makes 5 V. You'll find 1 fan in this package. Noctua NF-A4x20 5V Computer Fan Key Features The airflow of 5,53 CFM is sufficient for cooling down your computer Original appearance The powerful PC fan contains special bearings for a longer battery life Operating voltage: 5 V The NOCTUA Fan Is Ideal for Any Computer Case In order to safely operate the Noctua NF-A4x20 5V, you must have a 3pin connector.