This product is suitable for speed regulation of all car heaters; and stepless speed regulator for defroster.<br> Rely on the size of the overall current to control the size of the wind speed.<br> The advantage is that it is not easy to heat up, and the output power is large.<br> The 12V/24V universal is suitable for various models, and it is a good tool for adjusting the fan speed!<br><br> Product name: Automotive universal heater speed control switch (12V/24V universal)<br> Product parameters: <br> Switching voltage: DC 12V-24V<br> Rated power: 120W at 12V, 240W at 24V<br> Maximum current: 20A<br> Cable length: 6.0inch<br> Knob diameter: 0.78inch<br> Knob length: 1.25inch<br><br> Wiring method:<br> The red wire is connected to the positive pole of the power supply and the positive pole of the motor.<br> The blue wire is connected to the negative electrode of the motor.<br> The black wire is connected to the negative electrode of the power supply.<br><br> Product size: 2.16*1.89*1.30inch<br> Product weight: 0.46lb<br> Package size: 2.50*2.00*1.50inch<br> Package weight: 0.50lb<br><br> Package include: 1*DC speed motor controller