WeatherFlow WEATHERmeter for Precision Shooting - Proptics
WeatherFlow Wind Meter Anemometer for Smartphones
Amazon.com : WeatherFlow - WEATHERmeter- A Wireless, Handheld Weather Station - captures Highly Accurate Wind, Temperature, Humidity, and Pressure Measurements. No Internal Compass, Uses Mobile Device for Compass : Patio, Lawn & Garden