$14.49 – Working temperature 0℃~55℃, Protection level IP67, Product size 50x17mm, Product net weight 23g, Executive standard Q/QLMLO15, Wireless connection Bluetooth version 5.0, Battery type CR2032, Product model SJWS01LM, CMIIT ID 2020DP5425.
Right now the best price with coupon code for Xiaomi SJWS01LM Flood Water Immersing Sensor is $14.49 (in Banggood). Go down and check coupons out. Remember to check price history if it is available. Best price?
Latest price update (UTC time):
Banggood ($14.49)
Banggood warehouse is located in China. I couldn’t find any coupon for this product on latest product update. Is it expensive? Well, this price is higher than average price ($13.63)
Link: Banggood product page
Price: $14.49
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/i1u
Old coupons (from the oldest to the newest): BGXIAOMI664, BGYJ001, BG13767, BGXIAOMSA, BgcLuBofErtA10, BGXMCN51, 13f142, BGBTJU23, BGBTJU15, BGBTJUE6, BGMA030805, BGMA2902, BG10OFFAFF, BGAP2703, BGwhielabel, BGPL111, BGJUY281, BG10OFFAFF1, BGSE0101, BGOCXP136, BANGGOODSD, BGD11044, BGNOXP243, Terence, 2203ActiesNL, BG1efeb0, MVC8SPRING, BGJUNEGSG9
(these coupons are old, so probably won’t work)
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.
Price history and price alert
Here is price history (for all/most countries) for Xiaomi SJWS01LM Flood Water Immersing Sensor. The lowest price was: $12.55.
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)).