DESKTOP DIAL: Built-in ambient light sensor in the Desktop Dial enables you with simply one touch for the best brightness level; Let the auto-dimming function does the job! You can also manually adjust the brightness and color temperature any moment. Easy to use with precision. (Remove Protection Sponge Before Using It, Or It Will Impact The Function Of Power On/ Off) SPACE SAVING: Breakthrough design mounts on top of the monitor, saving valuable space on your desk USB POWERED: ScreenBar Plus e-Reading Lamp can be powered by USB port with power supply 5V/1A, ScreenBar Plus resumes your last used brightness and color temperature settings to welcome you back! NO SCREEN GLARE: Its asymmetrical optical design only illuminates the desk and eliminates reflective glare off the screen found on most regular desk lamps HUE ADJUSTMENT: Dial in the perfect color temperature for focus and comfort; Warm light for relaxing, cool light for work efficiency FITS NEATLY MOST MONITORS: The weighted clip gently rests on nearly any monitor with thickness from 0.4" to 1.2" (1 to 3 cm); It works perfectly on monitors with the bezel wider than 0.8cm (0.32”). The length of USB cable is 1. 5M.