2pcs 12V/24V DC Motor Speed Controller Universal, Knob Screw Electronic Stepless Speed Regulator Switch Versatile Application: This DC motor speed controller is designed for automotive use, effectively managing fan heaters, defrosters, and other automotive fans. It supports both 12V and 24V systems, handling up to 120W at 12V and 240W at 24V for reliable performance. Advanced Construction: Built with a durable heat sink, this electronic stepless speed regulator improves heat dissipation for extended controller life. The rotary knob allows smooth and precise speed adjustment, offering easy control for various applications. Hassle-Free Installation: Simple wiring connections—connect the red wire to the positive terminals of the power supply and motor, the blue wire to the motor's negative terminal, and the black wire to the power supply's negative terminal. Ensures a secure and efficient setup. Universal Usability: Suitable for a wide range of applications, from controlling fan speeds in vehicles to regulating DC-powered equipment. A practical solution for DIY users and professional technicians alike. Note: The actual product may vary slightly in color due to lighting and screen display differences, which does not affect functionality. Color: Black Material: Plastic Package Contents: 2 x Electronic Stepless Speed Controller (Only the items listed above are included; other accessories are not included) Note: Lighting and display settings may cause slight color variations. Measurement error allowed is +/- 1-3 cm.