A marine monocular is perfect for fans of sea tours, fishing and small boat owners. A compact optical tool has 8x magnification and an aperture of 42 mm. It helps to see remote objects well. This monocular is also excellent for studying close objects; its close focus is 3 m. The monocular shell has a built-in compass and a rangefinder. There is no dial illumination and thus, we recommend using a compass during the daytime with sufficient natural light. You can calculate the distance to the object with a known size using the rangefinder with a special formula, or calculate the size (height) of the object with a known distance. You can see the arch dial in the eyepiece. The compass indicates the direction to the object in degrees. Division value is 1°. North is 360°, South is 180°, East is 90° and West is 270°. The optics are made of high-quality BaK-4 glass. The lenses are fully multi-coated, providing a high quality, bright image even on a nasty day. The waterproof shell is made of plastic. It is filled with nitrogen to prevent the lenses from fogging. This monocular provides a wide field of view of 120 m at 1000 m distance. Eyepiece diopter adjustment in a wide range is available. We recommend using this monocular with the Levenhuk FS10 Floating Strap near water: the bright accessory will prevent the optical tool from sinking or getting lost.Optics material: BaK-4 glass. Optics coating: fully multi-coated. Eyepieces: 2 optical elements in 1 group. Objectives: 3 optical elements in 2 groups. Magnification: 8x. Objective lens diameter (aperture): 42 mm. Field of view: 7°. Relative brightness: 27.56. Twilight factor: 18.33. Exit pupil diameter: 5,25 mm. Eye relief: 23 mm. Close focus: 3 m. Eyepiece diopter adjustment: ± 4 diopters. Waterproof specification: yes. Body material: plastic. Eyecup: twisted-up. Additional: built-in compass and rangefinder. Field of view: 120 m/1000 m. Operating temperature range: −20…+55 °C. The kit includes: monocular, objective lens cap, cleaning wipe, strap, pouch, user guide and lifetime warranty. Weight: 0.445 kg. Package size: 18 × 9 × 7 cm. Warranty: lifetime.