$12.99 – 16.4ft / 32.8ft / 65.6ft Colorful USB LED Decorative String Lights with App Control Bluetooth Remote IP66 Waterproof for Holiday Room Decoration – 20M.
20m Colorful USB LED Decorative String Lights with App is for $12.99 (in Banggood). Go down and check coupons out. Remember to check price history if it is available. What is the best price?
Latest coupon and price update (UTC):
Banggood ($12.99)
Banggood warehouse is located in China. There are no active coupons for this product, but the price is pretty low isn’t it? Well, is it a good price anyway? From what I can see this price is higher than average price ($11.32).
Link: Banggood product page
Price: $12.99
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BG02ac06, BG8e78b0, BGb92f92, BGffc430
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
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.
Price history and price alert
Here is price history (for all/most countries) for 20m Colorful USB LED Decorative String Lights with App. The lowest price was: $9.99.
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)).