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.
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.
Updated:
Banggood
Warehouse in China.
Link: Tuya WIFI Temperature Humidity Smart Sensor
$20.67 with coupon: BG589b2e
Additional Banggood coupons:
1. First page
2. Second page
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)).