ThreeColor Light Alarm SystemDecibel meter with data logging uses green, yellow and red LEDs to indicate low. Medium and high noise levels and allows users to manually set alarm thresholds to improve the usefulness of the alarm PC Connectionsound level meter can record up to 43,000 data, which can be viewed on both the host computer and PC, as well as connected, data exported, analysed and printed. Sound meter can be recharged by USB LCD DisplayNoise decibel reader is equipped with a large backlit colour LCD display which shows the date and time clearly and graphically, making it easy to read. Sound decibel meter has a measurement range of 30130dB Dual Weighting ModesThe decibel meter with alarm switches between A and C frequencies. sound meter offers versatility for different sound environments. Measurement response is simultaneously fast and slow adjustable, and is equipped with a DC output MultifunctionDB meter accurately measures sound levels from 30 to 130 dB with a measurement accuracy of 1.5 dB.Sensitive response and adjustable settings. db meter is suitable for a wide range of environmental noise monitoring