Price history, coupons and price alert are available on this page. You probably want to know what is the best price?
etc. Recommend replacing cycle: 3 – 6 months, organic matter, heavy metal, bacteria, The filtering coverage area: 33 square meters The filter can remove 99.99 percent of PM2.5 particles
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 and price update (UTC):
Banggood
Banggood warehouse is located in Europe 
. I can’t tell you if this price is good – not enough records in my database, so I won’t judge.
Link: Banggood product page
1. ($38.99): BGAPEHGD
2. ($44.99): BG10OFFAFF
3. ($48.99): 13f142
paste coupon code in your cart and click Apply after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGair1S, bgchinafest, BGnowyfiltr, BGBFAFF2019, BGCITYADS2019, BGHOMEAPP, BGMPB2020, bGhOnEy10, BGAFF7OFF, BGSS10%SW, bgshOOp10, BGXMfilterS1, BGHome15%, BGHOMEAPP12, BGS1XMCZ, BG9XMfilterS1, BGHOMEAPP13, BGXMS1CZ, BGXMFLS1, BGHOMEA13, BGMJAP11, BGS1APFCZ, BGXMS1FLCZ, BGwhielabel, BG6a088e, BG2dd9ee, BG10OFFAFF1, BANGGOODSD, BG9dc3df, 00c906, BG00c906, 8Couponsde, MVC8SPRING
(you can check these old coupons out, but these probably won’t work)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. China – Original Green Xiaomi Mi Air Purifier 2 Filter Enhanced Version ($-3)
Price history and price alert
It doesn’t make sense to generate price history chart, because there is one price record which is: $39.99.
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)).