Price history, coupons and price alert are available on this page. What is best price?
Package Weight: 0.32kg, Product Types: Vacuum Cleaner Parts, Material: ABS, Fit Model: Roborock S4 S5 S6 E4 E20 E25 E35 S50 S65 Xiaomi Mi Mijia Robotic Vacuum Cleaner
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):
Banggood
Banggood warehouse is located in China. So I have checked for active coupons (all category coupons and old ones), but there was no working coupon in Banggood.
Link: Banggood product page
Price: $-3
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!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): Cuponation9, BGAHPU13, BGeaf456, BG00c906, BG589b2e
(probably won’t work, but you can try them out)
Price history and price alert
Check out price history chart (for all/most countries) for 20pcs Replacement for Roborock Vacuum Cleaner.
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)).