Power Source LED.
You can create price alert here, copy coupons and view price history. What is the best price?
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. I’m afraid that there’s no working coupon in Banggood.
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!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/i1u
Old coupons (from the oldest to the newest): 502C6B, 4d9d57, TTxBG10, BGOD1, 2019SPEDM, AFfbG10, BGcamp15, BGBFAFF2019, BGCITYADS2019, BGOC148, BGVDay10%off, bGhOnEy10, BGdragonBoat, BGCAMP01, bgshOOp10, BgoFErTaSchInA10, BgcLuBofErtA10, BGZPBC15, BGTY704CP, BGCuponation10, BGHONEY2110, BG10OFFAFF, BGwhielabel, 13f142, BG10OFFAFF1
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for 30W USB Solar COB LED Flood Light. The lowest price was: $5.99.
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)).