Earphone Acc. Washable Elastic Earphone Headphone Headband Cushion Protective Top Pads Cover. It is used for the host without low frequency (RCA) output (such as: cassette player/card machine/CD/VCD/DVD, etc.) to convert the high frequency output of the speaker to the low frequency (RCA) output, which is used to connect the car power amplifier or subwoofer signal enter.
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