... , school and construction site. * This meter is featured with wide measuring range (30 ~ 130 dB), A frequency weighting, Maximum function and ... darker. The darker the environment, the brighter the illumination.Specifications: Measuring Range30dBA ~ 130dBAAccuracy-1.5dB ~ +1.5dB(91dB@1KHz)Frequency Range31 ... alkaline Battery is Not included. DIGITAL SOUND LEVEL NOISE METER Measuring