When I was updating this page, then coupon price was $15.49 for BSIDE BTH81 Temperature Humidity Data Logger (in Banggood). Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
Power: 1x CR2032 Battery(Not Included)., Humidity range: 0-100%., Temperature accuracy: -10℃-70℃±0.5℃/0.9℉;-40℃-10℃±0.8℃/1.5℉., Humidity accuracy: 35%-80%±3.0%; other±5.0%., Connect interface: USB., Record interval: 1s-24hour (adjustable)., Temperature range: -40℃-70℃/-40℉-158℉., Export format: PDF & Data graph., Humidity resolution: 0.1%., Temperature unit: ℃/℉., Temperature resolution: 0.1℃.
Latest price update (UTC time):
Banggood ($15.49)
Banggood warehouse is located in China. There is no active coupon in my database right now (for Banggood). Is it expensive? This is the best price in history according to CouponsFromChina database!
Link: Banggood product page
Price: $15.49
This is the best price ever noted in my database!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGGines, BGTOOS729
(I don’t think these’re gonna work, but you can try ’em out anyway)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for BSIDE BTH81 Temperature Humidity Data Logger.
Price records source(s): 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)).