Water-resistant Protective Film Skin for Air Laptop.
Just check coupons out (with price alert and history). Do you want to know what the best price is?
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 China. There is one great coupon!
Link: Banggood product page
1. ($4.64): 2203ActiesNL
this code has to be applied in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): TTxBG10, BG3CSUM, AFfbG10, BGBFAFF2019, BGCITYADS2019, BGAFF10OFF, BGTT10, bGhOnEy10, BGdragonBoat, BgoFErTaSchInA10, BgcLuBofErtA10, BANGGOODSD, 00c906, BGef96eb, Kortings10, 2022ACTIESNL, Terence, BG1efeb0, MVC8SPRING
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Price history (for all/most countries) for Xiaomi Crystal Keyboard Cover 13.3inch is here. The lowest price was: $1.72.
Price records source(s): Gearbest, 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)).