Capacity: 3ml / 5ml, Thread: 510, Diameter: 22.2mm.
Price history, coupons and price alert are available on this page. What is best price?
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest price update (UTC time):
Price history and price alert
Here is price history (for all/most countries) for Vapefly Galaxies MTL RTA TPD Version Silver. The lowest price was: $19.99.
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)).