uni-t Digital Sound Level Meter,Decibel Meter, Digital Sound Level Meter 30-130dB Audio Noise Volume Measure Device Free App for iOS/Android, Max/Min Fast/Slow Data Hold LCD Backlit Auto Shutdown Non-magnetic Surveyor's Level  (15.4 cm)

UNI-T decibel meter sound level reader UT353BT (Bluetooth version). Measures from 30 dBA to 130 dBA. +/- 1.5 dBA with 0.1 dBA resolution. User-friendly interface. White backlit and clear LCD screen for easy visibility in dark situations IENV APP for IOS (8.4 & above) and Android (4.3 & above). Requires Bluetooth version above 4.0 and internal storage over 1 G. Supports data export (pdf file/excel sheet/trend curve image). With simple guide. Customized & Precise. Adjustable sampling time. Press FAST/SLOW to select between fast time of 125 ms and slow time of 1 s. Press Max/Min to switch maximum, minimum, or normal value measurement Lightweight & Compact. Easy to carry and store. Ergonomic design. Comfortable grip. 1/2 inch condenser microphone and wind screen foam. Short press HOLD/BL to record or exit data hold. Long press HOLD/BL to turn backlit on or off Versatile & Reliable. Widely used in noise detection, quality control, health control, environmental noise measurement in factory, industrial, traffic, office, home audio, music recording, neighbor noise complaints, speech therapy, etc