Need name of a special keybinding mod

[Fraternity]

Hey, i've seen a couple of vidios where people bind more then one key to a button.
For example S and 1 to use button 1 in action bar 2.
On the button it looks like S-1 or just S1. Anyone who know of an addon who can do this? Or something close?

[wereHamster]

Originally Posted by Fraternity On the button it looks like S-1 or just S1.

That means SHIFT-1

[Fraternity]

I uploaded a picture, there are some A-1, A-2 etc. there also. Can you explain that also?

[Fraternity]

Oh, the A-1, A-2 etc means ALT? (Ofc) So there are no mods so that you can make those kind of bindings with any letters you want?