Humidity Accuracy ±1% RH, Wi-Fi Support 2.4G IEEE 802.11 b/g/n, Temperature Measure Range 0℃-60℃, Power Supply DC 5V/1A, Measure Range 0% RH~99% RH, Size 65*65*17mm/2.5*2.5*0.6in, Temperature Accuracy ±1 Humidity, Weight 45.8g, Material ABS.
Get coupons, create price alert or check price history out! Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. One coupon is available. Cool!
Link: Banggood product page
1. ($20.67): BG589b2e
apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/i1u
Old coupons (from the oldest to the newest): BG21DC4, BGwhielabel, BGTUYA174, BGJUFR374, BGYR374, BGJUFO374, BGPDhome45, BG10OFFAFF1, BGTYOC374, BGISOG374, BGSPHOME35, BGTYSR374, BGTYSK374, BANGGOODSD, BGTYOU374, BGUdb49, BGUbf44, BGTYOP374, BGTYOI374, 00c906, BGJATY374, BG00c906, BGHealth10D, 2022ACTIESNL, BGHB218, BGGRMA156, BGMAYB234, BGXPAP67, BGGRAP141, 2203ActiesNL, BGHECARE1, BG2294d8, BG1c4b4a, BGHUXC038, BG77a473, BG4ee866, Cuponation9, BGb8a272, BG75597c, BG21b480, BGe7add4, BGfe422c
(there’s a little possibility that old coupon will work)
Price history and price alert
Price history (for all/most countries) for Tuya WIFI Temperature Humidity Smart Sensor is here. The lowest price was: $11.99.
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)).