Magnification: 2.5x. Objective lens diameter (mm): 40. FOV at distance 200 yards (ft/m): 162 / 49. Focus range (yards): 1.5 to infinity. Diopter adjustment (D): +/- 4. Detection distance (approx.) (yard/m): 250 / 225. Power supply options: CR-123 battery 3V (one). Estimated battery life w/out IR (hour): up to 60. Operating temperature (°F/° ): -22 to +113 / - 30 to +45. Water intrusion: Meets IPX4 rating. Humidity: Up to 93%. 7.09 in. W x 3.07 in. D x 2.36 in. H (0.95 lbs.). Instruction Manual . The Bering Optics Polaris night vision monocular features fully multi-coated optics. At 200 yards the field of view is more than 50 yards which makes it perfect for viewing moving objects and hunting varmints. The integrated powerful IR Illuminator enables clear viewing when ambient light levels are low. The ergonomically designed Polaris has a durable body with satin coating that makes it comfortable for extended operation. For additional convenience, the device comes with the wrist strap. Polaris features an automatic shut off when exposed to an intense light source for longer than two seconds. This protects the images intensifier tube from damage. This unique feature will not be found in any other similar Gen 1 devices in this price category.