Latest update shows that 400/600/800/1000/1200 Grit Diamond Sharpening Stone costs $4.99 (in Banggood). Check coupons or create price alert down below. Do you want to know what the best price is?
400/600/800/1000/1200 Grit Diamond Sharpening Stone Cutter Whetstone Grindstone – 1200#
Latest coupon and price update (UTC):
Banggood ($4.99)
Banggood warehouse is located in China. I don’t think there is an active coupon right now – at least in my database. Good or bad price? My database says that it’s pretty good price, coz average is $5.24.
Link: Banggood product page
Price: $4.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGWDT15
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Price history and price alert
Price history (for all/most countries) for 400/600/800/1000/1200 Grit Diamond Sharpening Stone is here.
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)).