Columbia 12" Automatic Fat Boy Finishing Flat BoxColumbia offers the widest range of high quality Finishing Boxes in the world. The Automatic Flat Boxes reduce the need to push the compound on to the wall. By engaging, the box springs put pressure on the compound chamber requiring only a light push to operate the box. Well built and fine tuned to offer great flat joints for years. We have been told for years that our boxes are the smoothest finishing and easiest to push. We are very proud to get