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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):
Multiple whirling dragon duct system, 18500pa wind pressure, 1100L / min air volume, Charge for 2.5 hours and run for 50 minutes, Built-in 2500mAH lithium-ion battery
Banggood
Banggood warehouse is located in China. I have no active coupons for you right now.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): e2bcea, 20OFFROIDMI, e19ae4, PICODICOM, d893c4, d9d5cc, BGRMF8, BGRM002, BGRMI8062, BGMPSO6, aff7off, BGROIDF87, BGRIF808, BGRM822, BFRMF8225, BGF8RM, BGRMF8M, BGBINKUPON8393, BGF8RMV, BGF8MR, BGFF8, BGRF8M, bGpAnDacHeCk, 1282291, BGCZF8, BGF8HM, BGHOMEAPP, BGCZRF8, BGF8HV, BGAFF7OFF, BGRMCF8, BGCZRF8Z, BGCZFR8, BGHCLE15, BGCZF8M, bgshOOp10, BGHOMEAPP13, BGHOMEA13
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Xiaomi Roidmi F8 Wireless Vacuum Cleaner [EU] ($-3)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi Roidmi F8 Vacuum Cleaner.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
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)).