ROM 128KB, RAM 144KB, Bluetooth v5.0, Operating Mode Full Touch, IP68, Model Mars 2, “7 Sports Modes Sedentary Reminder Calorie Burn Tracking Drink water reminder Alarm reminder Information Reminder”, “Heart Rate Monitor Blood Pressure Monitor Blood Oxygen Monitor Step calculation Sleep Monitor”, Main Control Chip DA14683, “Size: 1.4 inch Type: IPS Pixel: 240*240”, Compatible OS Android 5.0 and above; IOS 10.0 and above, “Dial Diameter: About 45mm Case Thickness: About 14mm Total Length: About 265mm Band Width: 22mm”, Brand NORTH EDGE, “Battery Capacity: 210 mAh Standby time: About 25 Days Charging Time: About 2-3 Hours”.
Price history, coupons and price alert are available on this page. 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 price update (UTC time):
Banggood
Banggood warehouse is located in China. There are no coupons available at this moment 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!
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): 6GSGIT, BGd2cd03, BG51f436, BG4161ec, BGc70579, BGAlerabat1, BGbf11dd
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for NORTH EDGE Mars 2 Smart Watch. The lowest price was: $17.58.
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)).