Yukon Tracker Night Vision Goggles Gen 1. Image intensifier tube classification generation 1. Magnification 1x. Lens diameter, 24 millimeters. Field of view, 30 degrees. Resolution (typical), lp/mm 32-36. Focus range, 1 yard to infinity. Eye relief, 12 millimeters. Diopter adjustment, diopter 4. Detection distance (approx.), up to 160 yards. Infrared illuminator effective distance, up to 100 yards. Power supply 3v (cr 123a). Estimated battery life (without ir), up to 30 hours. Operating temperature, -22 Fahrenheit to +104 Fahrenheit. Weight (w/out head gear), 13.4 ounces. Features: Hands-free operation, Compact, Extra wide field of view, Eclipse protective lens covers, Dual eye diopter adjustments, Central focusing, Built-in powerful pulse IR system infrared illuminator, Multi-coated optics, Rubber armor protection, weather resistant, limited lifetime warranty.