Mini Hidden Audio Recorder Voice Listening Device 96 Hours 8 GB Bug Recording UK. 18W/36W Aquarium Pond Fish Tank Sterilizer UV Lamp Light Clarifier/ Filter Pump. Maximum modulation: ± 75KHZ. A comprehensive solution to the use of KTV out of frequency, mixed frequency, sound-off, not enough distance, sound not into the microphone, singing is not smooth, battery is not durable, etc. problems.
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