0.4 to 20ms Wind measurement -20deg C to 60deg C temperature measurement 0.1deg C resolution deg C & deg F switchable Auto standby Low battery warning Backlight for low light use Hold function to record the Max & Min figures recorded Average function to record the average Specifications WIND VELOCITYRange 0.4 to 20ms 80 to 4000ftm Accuracy plusmn 0.2ms 2 of readingplusmn 40ftm 2 of reading Resolution 0.1ms 1ftm AIR TEMPERATURERange -20deg C to 60deg C-4deg F to 140deg F Accuracyplusmn 0.5deg C for 0deg C to 45deg Cplusmn 1.0deg C for -20deg C to 0deg C 45deg C to 60deg Cplusmn 1.0deg F for 32deg F to 113deg Fplusmn 2.0deg F for -4deg F to 32deg F 113deg F to 140deg F Resolution 0.1deg C 0.1deg F Accuracy 18deg C to 28deg C 64deg F to 82deg F 75 R.H. Temperature Coefficient 0.1 times the applicable accuracyspecification per deg C out of 18deg C to 28deg C Measurement rate 1 timesecond Operating environment 0deg C to 50deg C at 70 R.H. Battery 2x AAA Supplied Battery Life 50 hours typical with alkaline battery. Dimensions 25x 51x 133mm Tx Wx H. Weight Approx.116g including batteries.