Features: It is designed according to following standards, International Electrician Committee Standard: IEC 651 TYPE 2 and ANSI 1.4 TYPE 2.  With modern compact and portable appearance design.  Accuracy up to ±1.5dB.  Maximum value holding function to lock up the maximum reading.  Large LCD screen with digits reading.  Equipped with a sponge ball.  Auto power off design for energy saving.  Auto backlight display.  Portable, easy-to-use and handy instrument for sound quality control in factory, 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: 4digits   Resolution: 0.1dB   Sample rate: 2 times or second   Microphone: 1 or 2 inch electret condenser microphone   Max hold: MAX   Power supply: 9V battery (the battery is not included)   Power life: About 30 hours (alkaline battery)   Operating condition: 0-40℃ 10-80 percent RH   Storage condition: -10- and60℃ 10-70 percent RH   Product weight: 105g   Package weight: 130g   Product size: 14.2 x 5.3 x 3.5cm   Package size: 15.2 x 6.0 x 4.2cm    Package list: 1 x Sound Level Meter   1 x Sponge Ball   1 x User Manual Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.