1. Compatible with Raspberry Pi 40P pins, directly plugged in and used. 2. The switch controls the cooling plate fan. It is recommended to keep it on when using Raspberry Pi 4B. 3. Increase the height difference between the radiator and the motherboard, expand the negative pressure area, and dissipate heat more effectively 4. Increase the range of airflow, speed up heat dissipation, inhale at the bottom and exhaust at the side. 5. The hydraulic bearing fan is used, which has lower operating noise and longer service life than ordinary fans Name: for Raspberry Pi 4B cooling fan Compatible with: Raspberry Pi 4B Temperature range: -10+80C Bearing structure: hydraulic bearing Voltage: DC 5V Colour:black Material:plastic Package Contents: 1 x for Raspberry Pi 4 cooling fan Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.