When you driving car or motorcycle, for both wearing helmets, or the speed is very high, or to exercise various situation in a very noisy place, use this interphone can effectively communicate with the other one to avoid head turning problem.
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<br />Power supply: 2 x AAA batteries(not included)
<br />Frequence: 50-20000Hz+3 db
<br />Working Temperature: -20°C~50°C
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<br />Package Included
<br />1 x Motorcycle communication system host
<br />1 x Power cable
<br />2 x Earphones