The properties of graphene are to enhance high frequency, resolution, and balanced sound! Increase resolution! When the unit comes out of the factory, the middle hole has been pasted with tuning paper, but since each earphone shell is different, you need to open 3-4 earphone holes in a circle on the back cover to increase the air output, which can strengthen the high frequency. And the bass, that's the tuning! Plug Diameter: 3.5mm Whether there is a microphone: with microphone Wearing method: wearing ear protection Whether wireless: yes Headphone plug type: Bluetooth Whether wire control: no Compatible platforms: ANDROID iOS AliOS Windows Phone Impedance: 32Ω Sensitivity: 105dB/mW Frequency Response Range: 20-20000Hz Package: as your choose 2pc speakers or 4pcs speakers.
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