Aliexpress
There’re some similar items on Aliexpress in my database. There may be some other items though.
| Image | Product (link) | Price | Coupons |
|---|---|---|---|
 |
50m Automatic Garden Irrigation Watering System | 32.32 USD | – |
 |
Batery 4 AA Garden Smart Irrigation Wifi Water Timer | 36.14 USD | – |
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (19.99 USD): BGdfd47d
Coupon (28.19 USD): BG589b2e
(CouponsFromChina.com tip: apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BG34ad22, BG6b8c54, BG24c034, Cuponation9, BGf4adab, BG8ReviTrage, BGcoupon8off, BGGutscheine, BG00c906, BG8OFFCOUPON, TTBLACK5, BGdbe184, BGf625a4, BG992aa9
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Garden Irrigation System 18m 138pcs.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).