Multicoated, aspherical eyepiece lenses and BaK4 prisms Deliver bright, high-resolution images under all lighting conditions.Generous eye relief For a clear and comfortable view, especially for eyeglass wearers. Includes turn-and-slide rubber eyecups.Fully waterproof/fogproof Nitrogen-filled and O-ring sealed.Smooth central focus knob Fast range of focus for quick viewing.Durable and protective, rubber-armored coating Provides a sure, non-slip grip, wet or dry.Specifications Focusing System: Central Focus Magnification: 8x Objective Diameter: 25 mm Angular FOV (Real): 6.3 degrees Angular FOV (Apparent): 47.5 degrees FOV at 1000 yds: 330 ft Close Focus Distance: 9.2 ft Exit Pupil: 3.1 mm Relative Brightness: 9.6 Eye Relief: 15.5 mm Size (Length x Width): 3.9x4.5 in Weight: 12.5 oz Interpupilary Distance: 56-72 mm Waterproof, Fogproof Porro Prism Key Features: 100 percent waterproof/fogproof Compact and lightweight Aspherical eyepiece lenses provide crisp, distortion-free field of view Long eye-relief for eyeglass wearers Rubber armored, polycarbonate body Eco-glass lenses and prisms for high performance and weight-savings Twist-up eyecups for easy viewing Multicoated, Eco-Glass optics; 25mm Objective lenses 8x Magnification Large 330-foot Field Of View at 1000-yard distance Waterproof/Fogproof Porro Prism system