4500 Pocket Weather Meter - Olive Drab Night Vision. The Kestrel 4500 Pocket Weather Tracker is Kestrel"s flagship meter. Capable of monitoring and reporting an exhaustive list of environmental parameters - from temperature to barometric pressure, dewpoint, wind chill, and more**, the Kestrel 4500 is the most feature-rich pocket weather meter in the entire Kestrel catalog. In addition to the Kestrel 4000"s extensive list of capabilities, the Kestrel 4500 has these distinct monitoring functions: Digital Compass Wind Direction Crosswind Headwind/Tailwind These added features make the 4500 the Kestrel Meter of choice for military professionals, HAZMAT teams, and flight crews. Like all the pocket weather meters in the Kestrel 4000 series, the Kestrel 4500 is capable of storing and charting up to 1400 data points for later analysis. For military professionals, the Olive Drab NV version of the Kestrel 4500 features a night-vision preserving backlight. Backlight incorporates optical filter to reduce overall brightness and minimize blue and green spectrum light to preserve night vision. (Note: This backlight appears soft greyish pink, not "red", and is still in the visible spectrum, so is not compatible with night-vision equipment.) For military professionals, the Olive Drab NV version of the Kestrel 4500 is equipped with a red night vision backlight. The backlight appears as a subdued, almost white-pink hue. This is not an issue with the meter - this is how the light is designed for optimal performance in low-light conditions. Weekend shooters and military snipers alike have been calling for a Kestrel Meter with crosswind calculation for years - and the Kestrel 4500 meets that demand completely.