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Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There are no coupons available at this moment in Banggood.
Link: Banggood product page
Price: -3 USD
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
Old coupons (from the oldest to the newest): BGBLMCB1, BgcLuBofErtA10, BG15SH12, 13f142, BGAFF10OFF, BGSTHO15, BGded8d5, BGHONEY2110, BGed9fbe, BGSHOM15, BGe0b95a, 6GSGIT, BG81cd52, BGD11070, BGf8dce8, BGB5081, BG3c1bfb, BG6579cf, BG360c64, ADMITAD2212, BGSmart6, Couponsde7, BGf093e4, Cuponation9
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Broadlink BestCon MCB1 Smart Switch.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).