The Trigon180° Adapter Plate is for users who already own the center hub version of the Radius360°. Packaged with the Trigon180° cast aluminum adapter plate and foam pad, this plate is ready to snap into the center hub of your Radius360°sanding tool, instantly creating a corner and detail sander. The Trigon180° Adapter Plate can also be used with the Pro Handle Adapter creating a hand held corner tool.