Measures sound levels, light levels, airflow, %RH and temperature.A cost-effective introduction to aid conformance to health & safety in the work place.LCD display has a backlight, large digits and function indicators.Auto Ranges for sound with A frequency weighting.Cosine corrected silicon diode sensor for lux levels.70mm Vane for airflow.Semiconductor sensors in the probe for humidity and ambient temperature measurements.C or F temperature measurements.Standard 4mm camera bush for tripod mounting.Supplied in a briefcase carry case with lux probe, 70mm Vane, humidity/temperature probe, wind muffler and battery.