Extech SL510
It's never a good idea to guess with measurements, that's what measuring tools are for. No need to look for a power outlet, since it runs on batteries. Just get at it!
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Extech SL510 Sound Level Meter, Green
£131.72
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Extech Sound Meter
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Conrad Electronic
Extech Sound level meter SL510 35 - 130 dB 31.5 Hz - 8000 Hz
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