Latest update shows that 15m Micro costs 22.99 USD (in Banggood). Just check coupons out (with price alert and history). What is the best price?
Latest coupon and price update (UTC):
Banggood (22.99 USD)
Banggood warehouse is located in China. So I have checked for active coupons (all category coupons and old ones), but there was no working coupon in Banggood. Low/high price? Well, this price is higher than average price (14.49 USD)
Link: Banggood product page
Price: 22.99 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGb07d61, Terence, BGEP074, BG9c417e, BG691b01, BGd52a14, BGLMW5, BGde941d, BG35c3f4, 8Couponsde, BG8ffeb7, BGcce579, BG7273ee, BG4b795e, BGdbba48, 8BGwbg2204, BG2b7efb, BGHUMA074, BGHU2MA074, BGa9bb8d, BGMX276, BGHUXC101, BGfd0770, BGb3466a, Cuponation9, BG8ReviTrage, BG00c906, BGdbe184, BG589b2e, BGf625a4, BG41e360, BG51c595, BG23ALEAprD, BGe3b7b9, BGc89c0d, BG081591
(you can check these old coupons out, but these probably won’t work)
Aliexpress
Click here… to search for 15m Micro Drip Irrigation Kit on Aliexpress
Here are coupons that you can use.
Price history and price alert
Here is price history (for all/most countries) for 15m Micro Drip Irrigation Kit.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).