1x Relay module.
Basically copy coupon, view price history or create e-mail price alert. What is best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
| Image | Product (link) | Price | Coupons |
|---|---|---|---|
 |
ESP8266 ESP-01 5V 12V 1 2 4 Way WiFi Relay Module Things Smart Home Remote Control Switch 1Channel/2Channel/4Channel WIFI Relays | $3.93 | – |
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
1. ($9.39): BG00c906
this code has to be applied in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): 2203ActiesNL, BGJUNEGSG9, Cuponation9
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for 5V/12V ESP8266 4 Channels WiFi Relay. The lowest price was: $9.09.
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)).