"With the push of a button, you can deactivate the ADF cartridge and activate the shade 4 grinding mode (indicated by a blinking LED light inside the helmet), all without removing your helmet. External controls allow the user to control all shade cartridge settings to meet the welding procedure and personal preference. Adjust the shade level control knob to select the shade within settings of 5-9 or 9-13. Also features spherical front cover lens for high-optical quality. Suitable for all arc welding applications. Warning: Not suitable for laser and plasma welding. Meets ANSI Z87.1-2003 High Impact."