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Click here… to search for Xiaomi Miaomiaoce MHO-C601 E-ink Thermometer Hygrometer on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (10.99 USD): BGd6179a
(CouponsFromChina.com tip: coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGXIN374, BGDEAL374, BGHU0085, BgcLuBofErtA10, BGOCFO374, BGNOFR374, BGELEHOME20, BGNOTD374, BGBFHOME35, BGDEALBF374, BGDETD374, BGAFF10OFF, BGMARFR374, BGMASE374, BGCuponation10, BGMRDC52, 13f142, BGAPSE374, BGAPDEAL2, BGAPFO374, BGHONEY2110, BGAPF374, BGNIT374, BGMAYSE374, BGMMCDE, BGSP374, BGMAYTD374, BGMU374, BGFFO374, BGJUTD374, BGwhielabel, BGPDhome51, BGLYFO374, BGTYC374, BGDL374, BGTYSP374, BGSPHOME39, BGTYSY374, BGNDH06, BGUdb53, BGUbf48, BGCZOU374, 00c906, BGXN374, BG00c906, 2022ACTIESNL, BGHB218, BGMAYB240, 2203ActiesNL, BGHECARE1, BG4ee866, BG6d8139, BG1260aa, BG0278c9, BG5467eb, Cuponation9, BG75597c
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Here is price history (for all/most countries) for Xiaomi Miaomiaoce MHO-C601 E-ink Thermometer Hygrometer.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).