The APT-5035 4-in-1 environment meter is a cost-effective introduction to aid conformance to health & safety in the work place. It measures sound levels, light levels, %RH and temperature. The LCD display has large digits and function indicators. 2 ranges for sound with selectable A or C frequency weightings Cosine corrected silicon diode sensor for Lux levels Semiconductor sensors in the probe for humidity and ambient temperature measurements K-Type input for C or F temperature measurements 28mm LCD display with function indicators Data hold function freezes displayed value Max hold displays highest measured value Auto power off Low battery indication Standard 4mm camera bush for tripod mounting Supplied in a carry case with lux probe, humidity/temperature probe, K-Type wire probe, wind muffler and battery