By selecting the right setting for each task, you reduce eye strain and improve the quality of every weld. Specification: -Classification: 1/1/1/2 - Dark state: Shade 5, 8, 9-13 (variable) -Fail-safe state: Shade 5 - Light state: Shade 3 -Switching time: Light-dark: 0.1ms -Delay (switching time dark-light): User adjustable 40-1300 ms -Solar cell: No