Basically copy coupon, view price history or create e-mail price alert. What is the best price?
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):
Model GTR 2, Bluetooth Version 5.0, Customize Watch Face Support, Brand Zeblaze, Waterproof IP68 Waterproof, “Bezel: Aluminum Alloy Case: Zinc Alloy Band: TPU”, “Battery Capacity: 230mAh Standby Time: 14 days Using Time: 7 days Charging Time: About 1.5 hours Charging Method: Magnetic”, Incoming Call Support, Chip Realtek 8762C, Compatible System Android 6.0 or above; iOS 9.0 or above, “Size: 1.28 inch Type: LCD Pixel: 240*240 Pixel”, Operating Mode Touch Screen, APP GloryFit
Banggood
Banggood warehouse is located in China. Too bad there’s no coupon right now 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): BGba2c72, BGa17e50, BGGR2GTR, 6GSGIT, BG2e5635, BG11ANV05, BG51f436, BGBF1107, BG7a09c4, BG47296d, BG463f86, BGeda0d2, BGb891be, BGHUCJ153, BGc70579, BG2202FANS2, BG8fcda8, BGa1f5aa, BG4f175e, BG12e747, BG9a6da0, BG9f496c, BG03f663, BGf400e2, BG351382, BG7cd22a, BG4f51b8, BGbbb49d, BGHU2217, BGbf11dd, BGJP5333, BGJP333, BG6a733a
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Zeblaze GTR 2 Smart Watch.
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)).