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APP: fundo, Product process: zinc alloy + PC plastic, IP rating: IP68, Hardware, Bluetooth: Bluetooth 4.2, Chip: Nordic NRF52832, Brand: gocomma, Chip: Nordic NRF52832 (512Kb + 64Kb), Heart rate sensor, Waterproof: yes
Aliexpress
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Price history and price alert
Price history (for all/most countries) for Gocomma DT28 Fitness Tracker Silicone is here.
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)).