[Portable Sound Level Meter] A useful gadget, ideal for noise pollution monitoring, home theatre set-ups, health and safety standards, vehicle noise testing and much more. [HD Digital LCD] A large readable LCD display with backlight for quick and easy to read display of measurement results. [Power Supply] Power supply is 3 x AAA batteries (included), low battery indicator, automatic power off after 10 minutes, no need to operate, convenient and power saving. [Note: In order to install the batteries, the weatherproof ball and protective case must be removed]. [Versatile] Measuring range 30 - 130 dBA. Max/min/data hold function; automatic power-off; battery indicator; direct check of remaining battery. [Wide Range] Designed to meet the requirements of sound quality control measurements in a variety of environments. Ideal for testing music recordings, neighbor noise complaints, industrial environments, office environments, speech therapy, etc.