Super Quiet: This fan will not make you feel uneasy during they are working, but also a quiet experiment environment for you. Unique Terminal Interface: Come with two terminals, Their connectors are separated, One-to-Two interface, you can choose 3.3V or 5V. According to the voltage requirements in accordance with your needs to choose to use. Effective for Raspberry Pi or other experimental tools to quickly dissipate heat and will extend the working life of your other development board. Installation Screws Included: Don't need to purchase screws by yourself. Intimate service, easy to install! Widespread Use: for Raspberry Pi B/B+/A+/ 2/3 model B and B+ and Zero/Zero W other robotic projects and development boards. Specifications: Fan Dimension: 30x30x7.5 mm (LxWxH) Wire Length: 2.6 inches (66mm) Connector: One-to-Two pin Color: Transparent Operating Voltage: DC 3.3V - 5V Start up Voltage: DC 3V Suitable for Raspberry Pi or other development board. Used for used for Raspberry Pi 4/RPi 3/RPi 2/RPi Model B+ Package Included: 4 x Cooling Fan 16 x Nuts 16 x Screw