A Phantom Menace

I imported a DWG that was basically trash, but it was usable as a template for recreating a new object. However, when I export the new object into another file, the bounding box was far taller than expected, so I exploded it. Pic attached.

Best guess; this is some kind of remnant from the original DWG I used as the template, but I’m not sure how to clean it up since selecting it is beyond me. Once deselected, they just diappear, but I’d like to know if they are still in the file, and if so, how to clean it.

Go View and turn on hidden geometry then you will be able to select and delete them.

Thank you Mr. Box.