1. The switch controls the heat sink fan and LED lights, easy to use in the practical life. 2. Active cooling by fan has better effect than passive cooling, which is entitled with high performance according to rule. 3. Cooling fan is suitable for 4B, compatible with 3B and GPIO expansion board. 4. With more effective heat dissipation, heat sink fan is entitled with pratical adoptability. 5. Meanwhile, this cooler fan can be used for 4B or 3B and or 3B or 3A and , which is practical. Item Type: Cooling Fan Voltage: DC 5V Current: 0.2A colour:black Material:MetalandABS size:65x56x9mm Package Contents: 1 x Cooling Fan GPIO Expansion Board Only the above package content, other products are not included. Note: Light 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.