Power Supply for UR22 MKII?

Hello,
I just came to this forum,
As you know … this card has two power options, one via USB from a computer and the other from power supply…
and I’m interested…is there a official one power supply for this card…or which do you recommended for UR22 MKII?

This interests me because…sometimes i want to play through this amazing card when may PC shut down.