The small wheel assembly is the holder, 2" guide wheel, and small wheels only. This is for those who already own a Brodbeck Ironworks Platen or Quick Change Attachment.
If you do not have the Brodbeck Ironworks Platen or Quick-Change attachment, you will need one to hold the Small Wheel Attachment.
The small wheel attachment enhances your grinder's capability by using small radius wheels to get into those hard-to-reach places. It acts similar to a spindle sander.