The Kestrel 2500 Pocket Weather Meter has all the great features of the Kestrel 2000 with the addition of a pressure sensor. A three-hour pressure trend indicator helps you to predict fish and wildlife activity and know when the weathers going to turn nasty. Add in the easy-to-use altimeter and you have the perfect instrument for any outdoor activity! The night vision version of this model (Kestrel 2500 NV) has night-vision preserving backlight to help maintain the user's natural night vision. Features: Barometric Pressure Continuously updating three-hour barometric pressure trend indicator: rising rapidly, rising, steady, falling, falling rapidly Altitude Wind Chill Air, Water, & Snow Temperature Current & Average Wind Speed Maximum Wind Gust One-button clear and restart of Max Wind Gust and Average Wind measurement Waterproof & Floats Real-time hours: minutes clock Hold Function Aviation green electroluminescent backlight (Kestrel 2500) Night-vision preserving electroluminescent backlight (Kestrel 2500 NV).