I'm getting a power supply for my pedal board, and I've been looking at this one:

Problem is, the wall plug it comes with is UK style, and I need the US style wall plug. Luckily, it's a separate part (as you can see), but does anybody know what I'm even looking for in terms of what kind of cable that is? I don't even know what it's called and I'm googling around like an idiot. One end needs to plug into the box, with that trapezoid type shape, and the other end needs to plug into an American-style wall outlet:
