It utilizes a 1/2 inch electric condenser microphone to monitor sound levels from 30 to 130 decibels at an accuracy of +/-1.5dB with 0.1dBA resolution while reducing the effects of wind noise to produce more accurate readings. The MAX/MIN button will hold the highest/lowest reading until a much higher/lower reading is picked up. It will automatically power off after no operation for approximately 10minutes.Features: Measurement Range: 30dBA - 130dBA Accuracy Within +/-1.5dB Resolution: 0.1dBA Large LCD screen display auto power off Data hold function Max/Min sound level measurement Uses 3*AAA Battery Not includedSpecifications: Frequency range: 31.5HZ-8KZ Range: 30-130dBA Microphone: 1/2 inch electric condenser microphone Calibration: Electrical calibration with the internal oscillator Display: LCD 3 digits Package Include:1 x Sound Lever Meter