Dimensions: 4-3/4" Tall X 2-3/4" Wide X 1" DeepAir/Wind Speed Measurement Range: 0 To 5905 ft./min (0 To 30 m/sec)Air/Wind Speed Measurement Accuracy: 5 Percent Of ReadingAir/Wind Speed Units: km/h, mph, m/s, fps (ft./sec), knotsTemperature Measurement Range/Accuracy: 32 To 113 Degrees Fahrenheit (0 To 45C)/3.6F (2C)Auto Power Off Triggering Time: 10 Minutes Of Front-Panel InactivityOperating Temperature: 32 To 113 Degrees Fahrenheit (0 To 45C)@Power Source: CR2032 Battery (Included)Measures Or Calculates Ambient Temperature, Wind Speed And Wind Chill IndexDisplays Wind Speed Readings In Any Of Five Imperial And Metric UnitsSmall And Light Enough For One Handed OperationBacklit Dual-Readout LCDMax/Avg Wind Speed Memory + Data HoldFahrenheit/Celsius SwitchAuto Power Off (Can Be Disabled)Ideal For AC Monitoring