Solar Auto Darkening Welding Helmet US Flag Eagle Universal Auto-Darkening Welding Helmet; Viewing Area: 3.86" x 1.69" Cartridge Size: 4.33" x 3.54" x 0.35";UV/IR Protection: Permanent Shade DIN16; Light State: Shade DIN3(S777), DIN4(S7770a);Darkened State: Shade DIN 9 to 13 Variable Power Supply: Solar cells with built-in rechargeable battery; Power On/Off: Fully Automatic Sensitivity Control: Adjusts for varying ambient light and welding arc