The screen will have few to several faint small scratches, only visible upon close inspection or viewing/rotating under light.
The housing/bezel will have several blemishes (scratches, scuffs), visible upon quick inspection.
Compared to the A grade, the screen might show slightly more signs of use, and the housing will show more signs of use.
The screen will have numerous faint and a few more pronounced scratches visible upon quick inspection.
The housing/bezel will have several blemishes (scratches, scuffs) visible upon quick inspection.
The screens on the B grade will show more signs of use compared to the AB grade.