Feature: 1. Wide Application: The speed controller can regulate speed, temperature, voltage, and light. It is widely used in exhaust fans, filament bulbs, electric furnaces, angle grinders, marble machines, and blowers. Note: It cannot be used with electrical appliances containing circuit boards or capacitive electronic components, such as microwave ovens, induction cookers, rice cookers, water pumps, washing machines, LED, or energy-saving lights. 2. High-Quality Material: The variable speed controller features a high-quality ABS plastic insulated flame-retardant shell that resists discoloration, deformation, and cracking. It is heat resistant. Internal components are made of thickened phosphor bronze, ensuring safe, reliable performance and extended service life. 3. High-Precision Display: The fan speed control switch includes a precision voltage regulating knob with high accuracy and stable performance. Control accuracy reaches 1 volt. The digital display screen allows clear monitoring of the machine's working voltage. The LED light enhances visibility of real-time voltage readings. 4. Overload and Overvoltage Protection: The variable speed fan controller includes an independent switch with overload and short circuit protection. When the instantaneous current exceeds 15 amperes, the switch automatically powers off to protect the controller. The indicator light helps monitor the switch's operational status. 5. Back Hook Design: Designed for convenience during angle grinder use, the controller features a hook on the back. This allows it to be hung on a tool bag or kit for easy carrying and quick access. Plug-and-play design ensures simple and practical operation. Specification: Item Type: Electronic Voltage Governor Material: ABS Color: Black Package List: 1 x Electronic Voltage Governor