Piezoelectric underwater headphones "AquaSonos" with a passive voltage amplifier, for metal detectors. 
Frequency range 40-4000 Hz. 
These earphones for Minelab Excalibur II, 800,1000 metal detectors. 

They can stay under water for a long time. 
The depth of immersion is limited by the specific metal detector with which the headphones are used.
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Wire, length 95 cm. Stretches up to 165 cm.Increased mechanical strength.
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Headphones in the package. Photos without packaging are taken exactly the same headphones.
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Attention. These AquaSonos underwater headphones are sold only on Ebay. 
If you see them for sale elsewhere, they are scammers.




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