Features: Experience precise 0-12V stepless speed control with PWMs fan controller, featuring rotary potentiator switches for effortless 0% 97% duty cycle adjustment and instants start/stop operations to optimize airflows in PC builds. Engineered with industrial PWMs chips and 25kHz frequency, this controller delivers linears 0-100% speed regulation for 4pin CPU/case fans, while builts in overcurrent/short circuit protections ensures safe operations across 20°C to +70°C environments. for PC builders, gaming enthusiasts, and overclockers seeking thermal management solution for high performances rigs or workstation setups requiring customizable cooling precisions. Perfectly adapts to gaming PC, servers, or projects where stable airflows control is during intensive tasks like rendering, streaming, or extended gameplay. Simplify installations with its plug and play 4pin PWMs interfaces and high current terminals, requiring not software setup, effortlessly integrate into existing systems within minutes using basic tool. Specifications: Materials: Plastic Size:24x19mm Package Includes: 2Pcs Fan Speed Controller note: Please allow 0-1cm error due to manual measurement. make sure you not mind before bid. Due to the differences between different monitors, the Pictures may not reflect the actual of the item.