Talking time: about 4 hours, Battery capacity: 55mAh Lithium-ion battery.
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Price history and price alert
Here is price history (for all/most countries) for M163 Bluetooth Earphone. The lowest price was: $1.11.
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)).