Side view window and red reference line make you easier to read orientation data. The balanced design prevents it from tilting and rubbing against the window frame and causing it to jam in non-level conditions.The positioning post design allows you to rotate the scale ring to set the target direction. And the liquid-filled light-absorbing design allows it to absorb sunlight, lights and other light sources that it can emit night light in dark conditions.Made of plexiglass and ABS material, it is very durable for use.The length of the compass is 8.2cm, the width is 6.2cm and the height is 3.5cm.It is suitable for deep water operations, diving, underwater, water sports, guidance and so on.Item Name: Diving CompassMaterial: ABS,PlexiglassUnderwater Dive Depth: 50mPurpose: Underwater GuidanceFeatures: Convenient Reading, Luminous, Precise ScaleStorage Temperature: -22 Degree Fahrenheit-140 Degree FahrenheitUnderwater Working Temperature: -30 Degrees Celsius-60 Degrees CelsiusSize Details: Compass: 8.2cm x 6.2cm x 3.5cm/3.23" x 2.44" x 1.38" (Approx.)Spring Rope (Normality): 88.5cm/34.84" (Approx.)Notes:Due to the light and screen setting difference, the item''s color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x Diving Compass1 x Elastic Cord Strap1 x User Manual