You can create price alert here, copy coupons and view price history. 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):
IP rating: IP57, Bluetooth Version: Bluetooth 4.2, Screen resolution: 128x 32, Standby time: About 7 days, Battery Capacity: 91mAh
Price history and price alert
It doesn’t make sense to generate price history chart, because there is one price record which is: $89.99.
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)).