the Kestrel 2500NV has a night-vision preserving backlight which helps users to sustain natural night vision. The NV's backlight incorporates an optical filter to reduce overall brightness and minimize blue and green spectrum light to preserve night vision. Additionally, NV backlights are also much dimmer than a standard backlight, making it more difficult to detect with the naked eye in night operations. This backlight appears soft greyish pink, not red, and is still in the visible spectrum, so it is not compatible with night-vision equipment.

it takes 30 to 45 minutes for the average eye to adapt to darkness and maximize night vision. Even a short burst of white, yellow, green or blue light bleaches out the rod cell photoreceptors in the eye and causes night blindness until the entire adaptation process can take place again. Light in the red spectrum does not cause this bleaching out, preventing night blindness and night vision fatigue.

key features and functions

• current wind speed
• maximum wind gust
• average wind speed
• air, water & snow temperature
• wind chill
• barometric pressure
• altitude
• real-time clock
• protective cover with sure grip overmolding
• data hold function
• large easy-to-read display with backlight
• waterproof and floats
• innovative design for stability and accuracy in abrupt condition changes
• patented user-replaceable impeller
• quick response, external thermistor
• high precision pressure sensor
• reliable, portable, and easy to use

Kestrel 2500 includes

• a slip-on protective cover
• neck lanyard
• CR2032 coin cell battery (average life 300 hours)
• 5-year warranty
• Kestrel certificate of conformity