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Driver unit: 8mm, Frequency response: 20-2000Hz, Impedance: 16ohms, Sensitivity: 100 ± 3 dB, Headphone Sensitivity: 106db
Price history and price alert
Here is price history (for all/most countries) for Syllable D9x Wireless Headset.
Price records source(s): Gearbest
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You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).