Panel Size: 420*280mm /16.9*11.26in, Material: A-level polycrystalline silicon solar panel, Current: 0-1000MA, Maximum power: 20W, Detection Rate: IP65, Rated power: 10W, Maximum voltage: 21V, Working voltage: 18V.
Check coupons or create price alert down below. Let’s see what best price is ATM.
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.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in Europe 
. Sorry, but there’s no price history in my database. I found coupon for you. Check this out.
Link: Banggood product page
1. ($67.65): BGCarEle4
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Price history and price alert
It doesn’t make sense to generate price history chart, because there is one price record which is: $67.65.
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)).