You can get Folomov USB Battery for 11.99 USD using coupon code (in Banggood). You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
Latest price update (UTC time):
Banggood (11.99 USD)
Banggood warehouse is located in China. As you can see I didn’t find any active coupon for this product right now… I think you want to know if the price is good. From what I can see this price is higher than average price (10.12 USD).
Link: Banggood product page
Price: 11.99 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGFLKC, linepayflt, EYBG, BGBSFV, BGTORCH, BGLKA
(these coupons are old, so probably won’t work)
Aliexpress
Click here… to search for Folomov USB Battery Charger on Aliexpress
Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for Folomov USB Battery Charger.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).