I googled it and I have no idea what you are talking about.
I still don't get it.
Is it a parity?
Nikklas - like for centres on 6x6 or 7x7 - r' U' l U r U' l'
Use it to swap with a centre piece on another side, then use the sam alg with a setup move, to bring the original piece back into place. I know what I'm trying to say, just struggling to convey it.
What is it ? The Alg to inverse the center ?[r2:[r'B'r,f2]]