The SIT Surface Prep Welders Kit is for preparing a weld surface with crimped steel wire. That's the lighter-duty wire, which suits cleaning up a seam rather than stripping heavy scale. It's the only kit in the range, and it's a special-order item.
If you only need one brush, or you're working a different metal, the wire and nylon brushes are sold singly, with the brush buyer's guide to help you choose between them.
