describe: 100% pure Good performance--This voltage regulator has a fluctuation voltage absorption circuit, which can effectively protect high-power thyristors and ensure longer service life and durability. Wide Adjustable Range--With a wide voltage adjustment range, the output voltage can be easily adjusted between 50V and 220V. Wide range of applications - The voltage regulator can be widely used as a heat controller on electric stoves, water heaters, dimmers on lamps, speed controllers on small motors or temperature controllers on electric soldering irons, etc. Thus achieving the effects of dimming, temperature, voltage and speed. Make sure all power is disconnected before attempting to connect the controller. Package contents: 1 piece voltage regulator Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.