Single shade 3 (light state) /10 (dark shade).
Solar powered-no batteries to change. Constant UV/IR protection. Quick and easy installation-simply install the filter in your helmet with the clear protection plate in front. **Charge in direct sunlight for 2 to 3 hours. This welding filter is capable of use in virtually all welding environments with the exception of oxy-acetylene, x-rays, gamma rays, high energy particulate radiation, lasers or masers, and some low amperage applications. Clean your filter with pure alcohol. Use a clean, soft cloth in order to avoid scratching the highly polished lens surface. Operating temperature of the filter ranges from -10ºC (+14ºF) to 55ºC (+130ºF). Store in dry place with temperature range from -10ºC (+14ºF) to +40ºC (+104ºF). Inspect the protective plates and replace immediately if cracked, scratched, or pitted, to prevent injury. Inspect the filter frequently and immediately replace if worn or damaged. Warnings: If the welding fails to switch from light to dark, or should unexpected irregularities appear while welding, the filter must be replaced immediately. Always wear safety glasses for protection against impact.