-20℃~100℃ silicone material, L: 620ml, L: 180g, microwave heating..
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
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. I couldn’t find any coupon for this product on latest product update.
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/i1u
Old coupons (from the oldest to the newest): 99a5c21, 99a45c20, 99a5c29, 93e4ec, f9bc65, 99a5co, 502C6B, TTxBG10, BGOD1, AFfbG10, BGXM45, BGA61183, BGBFAFF2019, BGCITYADS2019, BGTS204, BGMPB2020, BGAFF10OFF, bGhOnEy10, BgoFErTaSchInA10, BgcLuBofErtA10, BGTY742TRL, BGCuponation10, BG10OFFAFF, BGwhielabel, BG10OFFAFF1
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi 620ml Hot Water Bag L Blue? There we go. The lowest price was: $9.09.
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)).