NRF51822 Chip, sleeping monitor, heart rate monitor, Ultra-long Battery Life.
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Price history and price alert
Do you need price history chart (for all/most countries) for NO.1 F6 Smartwatch? There we go. The lowest price was: $19.99.
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)).