Basically copy coupon, view price history or create e-mail price alert. What is best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Wireless Type: bluetooth, Support Memory Card: No, Control Button: Yes, Certification: CE, Codecs: Apt, Number Of Drivers: 2, Volume Control: Yes, Style: In-ear, Communication: Wireless, Driver Diameter: 10mm, Package List: Charging case, Active Noise-Cancellation: Yes, Vocalism Principle: Dynamic, Waterproof: No, Brand Name: KZ
Banggood
Banggood warehouse is located in China. There is one great coupon!
Link: Banggood product page
1. ($41.99): BG901a07
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BG9ba0e8, BGAUDIO, BG1b5830
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for KZ VXS Wireless Earphones.
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)).