ULTIMATE EYE PROTECTION:Auto-darkening filter switches from light to dark in 1/25000 sec, in event of electric failure, the welder remains protecting against UV and IR radiation according to shade 16.1/2/1/2 rating meets ANSIZ87.1-2010 and EN3794/9-13 standards. A smart choice for safety MANUAL ADJUSTMENT MEETS DIFFERENT DEMANDS: Equipped with sensitivity and delay settings for adaptability for different environments and task durations; Enjoy enhanced visibility and color recognition.Light level of filter is DIN4 and the time from dark to bright state within 0.1s to 1.0s