Feature: 1. FUNCTIONAL DESIGN: PC 8 channels fan hub effectively lowers the fan speed when computer components are idle, reducing noise and power consumption. Conversely, it increases the speed when components are busy, lowering their temperature for optimal performance. 2. ADJUSTABLE CONTROLS: 4 knob cooling fan speed controller features independent speed controls, offering personalized adjustments for every users needs and preferences. 3. WIDE COMPATIBILITY: Cooling fan speed controller is ideal for a PC computer water cooling system with easy installation. It has a 4PIN interface (3PIN compatible) perfect for CPU, HDD, VGA, and PWM fans. 4. SPACE SAVING: PC 8 channels fan hub speed controller is designed to fit precisely in the PCI slot of a computer case, allowing for easy installation without taking up valuable space. 5. DURABLE MATERIAL: Made from quality plastic, metal, and PCB, our 4 knob cooling fan speed controller ensures long lasting durability and performance with low loss and heat generation. Specification: Item Type: PC Cooling Fan Speed Controller Material: Metal, Plastic, PCB Voltage Range: 0V-12V Supported Fans: 8 Fans (not included) Power Limit: 72W (theoretical value) Control Method: Manual Knob Adjustment Installation Position: PCI Slot Power Interface: 4Pin interface Fan Interface: 4PIN (compatible with 3PIN). Package List: 1 x Speed Controller 1 x Screw Note: The built in resistor of the speed controller may generate heat during use, which is considered a normal. Additionally, there is a power limit, and it is not recommended to connect violent fans with a power exceeding 10W individually, as it may damage the product.