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Built-in 3.7V 800mAh Li-ion battery, Charging time: about 15hrs, working time: about 2 – 3 weeks ,5 functions and 15 working modes,5 functional keys
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Price history and price alert
Here is price history (for all/most countries) for Smartsonic+ JK-T10 Electric Ultrasonic Toothbrush.
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)).