Can you Mirror an object?

Im trying to mirror a staircase for a castle but the spiral staircase only comes in one direction. I want two staircases at the entrance going up in opposite directions so i need to mirror the geometry of the pre made stairs.
im hoping that the only way isnt to build a new one from scratch

Have you tried setting the size value for x to -1.

I have now thank you that works. Still trying to figure out this program