For Dual Fan: - Low Power Consumption Design - Dual Cooling Expericnce, No More Overheating Problem - Very Quiet Cooling Fan, You Can Hear Even Nothing - All of the Fans were Tested by Our Engineer, Very Nice Quality Control - Update Thermal Tape Can Make Sure Best Heat Conduction Effect For Aluminium Alloy Case and Heatsink: - Perfect Size for Raspberry Pi 4 Model B - Big Size Heatsink and Cooling Fan Can Make Sure: No More Overheating Problem - High Quality CNC Aluminium Alloy Case Can Protect your Pi Safe - Open Design Can Make Sure Our CNC Case will not effect Wifi Signal Package Included: 1x CNC Aluminium Alloy Case With Dual Fan 1x Screw Set 1x Thermal Tape Notice: Raspberry Pi is NOT Included