The Dwyer SM100 Digital Sound Meter is ideal for measuring noise levels from 30 to 130 dB with accuracy of ±1.5 dB. The SM-100 has a frequency of 31.5 Hz to 8 kHz, three different dB ranges, and a 1/2" condenser microphone. This model has two frequency weightings: the "A" weighting ranges from 30 to 130 dB, while the "C" weighting ranges from 35 to 130 dB. The four digit LCD backlit display has the ability to update in 0.5 seconds when the unit is set to fast response. Model SM-100 features data hold, ability to record maximum/minimum, auto ranging, auto power-off, and a dynamic range of 50 dB. The compact size of the SM-100 makes it very easy to operate and store. The SM-100 is ideal for technicians measuring and recording sound levels in zones or rooms of buildings, musical halls, theaters and near equipment or machinery on the plant floor.