' Auto Darkening Welding Helmet, Lens Shade 4, 9 to 13, Graphics None, Color Black, Plate Height 1-9/16 In., Plate Width 3-3/4 In., Viewing Area 5.8 sq. in., Headgear Ratchet, Classic Series, Material Nylon, Grind Mode Yes, Number of Arc Sensors 3, ADF Controls Knobs, Power Source Battery and Solar, Battery Type Lithium, Battery Life 2000 hr., Electromagnetic Sensor No, Switching Speed 1/15, 000 sec. '