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Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
2000mAh, 18 hours of non-stop music per full charge
Price history and price alert
Price history (for all/most countries) for ZANMAX Bluetooth Speaker 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)).