3.86-inch x 1.73-inch viewing field * Shade DIN 9 to DIN 13 Variable with Grinding Model * 1/25,000 sec. reaction time * Permanent Shade DIN 16 for UV and IR protection. * Automamtic on/off with replaceable lithium battery * 1/25,000 second reaction time * Automatic on/off switch with replaceable 3V Lithium batteries * Large 3.86-inch by 1.73-inch viewing field * Shade DIN 9 to DIN 13 variable for welding; shade DIN 4 for grinding * Stepless adjustable knob sensitivity control