Durable? You bet. The 4000 has been subjected to impact, water submersion and extreme temperature tests, and keeps on working. Kestrel 4000’s have been put to the test in some of the harshest conditions on the planet. U.S. Special Forces, combat weather teams, wildland firefighters, smoke jumpers, Mt. Everest expeditions and IRL pit crews are just a few who rely on a Kestrel 4000 to provide them with the crucial environmental data they need. Watch the Weather Channel during a hurricane, and you’re sure to spot a Kestrel 4000 being wielded by an intrepid on-screen meteorologist.
Available in the NV Configuration
Military personnel and pilots flying in darkness are often concerned with preserving their night vision. Due to overwhelming demand from our military customers, the Kestrel NV line was added in 2005.
The Kestrel 4000NV is available with an Olive Drab case or a Desert Tan case. The unit 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 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.
