For Precision & Competitive Shooting - The Kestrel with Hornady 4DOF quickly and accurately determines long range holdovers and windage corrections to get you on target with first round hits. This all-in-one unit combines real-time environmental measurements with the 4DOF ballistics calculator for a rugged and dependable compact yet powerful long-range shooting tool. No more DOPE cards guessing at the wind or being unsure where your bullet will hit when you change elevation.
Environmental Measures : 
Altitude (Barometric)
Barometric Pressure
Compass Direction
Crosswind
Density Altitude
Dew Point Temperature
Headwind/Tailwind
Heat Stress Index
Relative Humidity
Station Pressure (Absolute Pressure)
Temperature
Wet Bulb Temperature (Psychrometric)
Wind Chill
Wind Speed/Air Speed