' Auto Darkening Welding Helmet, Lens Shade 4, 9 to 13, Graphics None, Color Red, Plate Height 3-9/16 In., Plate Width 4-1/3 In., Viewing Area 2 In. x 4 In., Headgear Ratchet, e650 Series, Material Zytel ST, Grind Mode Yes, Number of Arc Sensors 2, ADF Controls Analog, Power Source Battery and Solar, Battery Type Lithium, Battery Life 2500 hr., Electromagnetic Sensor No, Switching Speed 0.10 microseconds, Features Lens Speed 1/55, 555 sec., 3 yr. Warranty, Includes Protective Lens Covers '