Aomaso Digital Anemometer Wind Speed Gauge LCD Mini Handheld With Vane Sensor Measuring Wind Speed Air Volume Air Velocity Temperature for Model aviation, Flite Test, Kite, Sailing, Fishing and More Ideal for model plane pilots, shooters, hikers, and other outdoor enthusiasts. With large screen LCD display and backlight, easy to read data in dark environment with multiple units: mph, ft/min, Km/h, m/s or Knots, as well as temperature in Celsius or Fahrenheit. Aomaso Anemometer measures both wind speed and air temprature. Wind speed range: 1 - 25m/s; temprature range: 32F to 122F(0C - 50C. A reliable and replacale 9V battery is already installed in the gauge. No need to pay for an extra battery. Lightweight and compact body makes it so easy to carry along with. Even kids can handle and use it smoothly with just one hand!