SincereetaliDigital Sound Level Meter Decibel Recorder 30-130dB Features: It is designed according to the following standards, International Electrician Committee Standard : IEC 651 TYPE 2 & ANSI 1.4 TYPE 2. With modern compact and portable appearance design. Accuracy up to 1.5dB. Maximum hold function to lock the maximum reading. Large LCD display with digit reading. Equipped with sponge ball. Auto power off design for energy saving. Auto backlight display. Portable, easy to use and convenient instrument for sound quality control in factories, traffic, family and audio system. Specifications: Measuring range: 30-130dBA Accuracy: 1.5dB Frequency range: 31.5Hz to 8.5KHz Frequency weighting: A Digital display: 4 digits Resolution: 0.1dB Sampling rate: 2 times/second Microphone: 1/2 inch electret condenser microphone Maximum hold: MAX Power supply: 9V battery (battery is not included) Battery life: About 30 hours (alkaline battery) Operating condition: 0-40 10-80%RH Storage condition: -10--+60 10-70%RH Product weight: 105g Package weight: 130g Product size: 14.2 * 5.3 * 3.5cm Package size: 15.2 * 6.0 * 4.2cm Package List: 1 * Sound Level Meter 1 * Sponge Ball 1 * User Manual SincereetaliAre you still suffering from the following problems? The angle grinder is difficult to control, the stone size is not accurate, the dust is harmful to health.