The Raspberry Pi 4 Case Fan is an official Raspberry Pi accessory, designed to be used specifically with the official Raspberry Pi 4 Case. Great for over-clockers and other power users, it keeps your Raspberry Pi 4 at a comfortable operating temperature even under heavy load, avoiding CPU throttling and keeping your Pi 4 running at tip-top performance. It's the perfect add-on for anyone pushing their Pi to the limits with gaming, a media centre or other intensive projects. The fan is temperature-controlled via PWM (Pulse-width Modulation), with a user-selectable GPIO pin. The Case Fan also comes with a heatsink for the CPU, removing heat from the processor with the aid of the fan.