Aliexpress
Click here… to search for 6 Pcs 120mm RGB Fans with Music Controller [EU] on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in Europe 
. I’m afraid that there’s no working coupon in Banggood. I don’t want to misguide you about the price. I don’t know if it’s good, because I don’t have enough records in my database…
Link: Banggood product page
Price: -3 USD
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!
Old coupons (from the oldest to the newest): 2203ActiesNL, BG1efeb0, MVC8SPRING
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
There is only one database record (it was for 20.99 USD), so you can’t see price history chart.
You can set price alert (for Banggood).