Purchased 4 and used once for a research project so I no longer have any use for them. The 4 in 1 Environmental Meters measure Sound Levels in dB, Light Levels in Lux, Relative Humidity Levels expressed as %RH and Temperature Levels in deg C or deg F. The meter has a data hold and max hold button plus a low battery indication. At the base of the meter is a standard 4mm camera bush for tripod mounting. Price includes postage to anywhere in the UK. Thanks for looking.