Go down and check coupons out. Remember to check price history if it is available. Let’s see what best price is ATM.
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Ultralight PEI frame, Glasses width: 143mm, Package Contents: 2x Pair of Glasses, 2x Clean Cloth
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi 2x Ultralight Anti-blue-rays Protective Glasses? There we go.
Price records source(s): Gearbest
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)).