NDIR CO2 Sensor MH-Z14A PWM NDIR [EU] (Banggood, Aliexpress: NDIR CO2 Sensor MH-Z14A PWM NDIR Infrared Carbon Dioxide Sensor Module Serial Port 0-5000PPM Controller (the best price with coupon)).
Go down and check coupons out. Remember to check price history if it is available. What is the best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in Europe 
. Hmmm… There is no active coupon in Banggood at this moment. I don’t want to misguide you about the price. I don’t know if it’s good, because I don’t have enough records in my database…
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG37bdc2, BG8FORMULAMX
(these codes were not working in latest coupon update, but you can check them out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. China – NDIR CO2 Sensor MH-Z14A PWM NDIR ($-3)
Price history and price alert
Price history is not available for this item (not enough database records)! The lowest price was $16.99 though.
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)).