Just check coupons out (with price alert and history). Do you want to know what the best price is?
Rotation angle: 360 degree Max. Extensible width: 9.5cm Arm length: about 17cm Stick plate diameter: 6.4cm
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Price history and price alert
Price history (for all/most countries) for Gocomma Long Arm Car Cellphone Holder is here.
Price records source(s): Gearbest
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)).