That is very easy. It is called "two colons"
It is also an operator. For all of theses things type "help operators" and look all of the neat things you can do in PowerShell.
:: Static member operator
Calls the static properties operator and methods of a .NET
Framework class. To find the static properties and methods of an
object, use the Static parameter of the Get-Member cmdlet.
\_(ツ)_/