The Navigator with 50mm lens diameter and 7x magnification offers a stable image even in rough seas as well as guarantees bright images with excellent contrast and sharpness of detail in the dark. Legendary ruggedness, water pressure proof to 5 m.Features:Auto-FocusHigh-contrast opticsWaterproof up to 5 meters2 way valve nitrogen pressure systemRubber armouredCylindrical eyecups10 years warranty