Control APP: eWelink.
Go down and check coupons out. Remember to check price history if it is available. You probably want to know what is the 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 Europe 
. There are no active coupons for this product, but the price is pretty low isn’t it? This is new product in my database, so I don’t know if this price is good.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): elec, e2bcea, SONOFF15, BGE13, 13f142, bGpAnDacHeCk, BG9NY, BGVDay10%off, BGMPB2020, BGTT10, bGhOnEy10, BGSMOFF, BGSONOFF15, BGELIG0920, BgcLuBofErtA10, BGSONOFF16, BGAFF10OFF, BGSTHO15, BGCuponation10, BGHONEY2110, BGSHOM15, BGSHE15, 6GSGIT, BGSmart6, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BGJUNEGSG9, BG15Sonoff, BG8b589f, Cuponation9, BGHU2320, 9OFFSUMMER, BGXIFD222
(there’s a little possibility that old coupon will work)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. China – SONOFF Dual Channel DIY WIFI Switch ($-3)
Price history and price alert
Well, you won’t see price history chart, coz we have only 1 database record for this item (and price was $11.04).
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)).