DSM-1 Digital Sound Pressure Level (SPL) Meter

Highly accurate SPL meter with 2 level ranges measuring between 30dB and 130dB @ 32Hz-8KHz. Selectable A or C weighting and Fast or Slow response; maximum Hold selector with Hold button to capture input at any time; alarm indicating the input is above range; internal battery tester; built-in calibrated, linear omnidirectional 1/2" electret condenser microphone.