What does 'Grade B' condition mean?

These items are those that show signs of normal wear and tear. It will be a standard condition device, which may have dents and scratches to the rear case and screen from everyday use. No cracks or heavy damage. There will not be anything that will impede the usability.
Please bare in mind that the grade of a device is purely cosmetic and will is not related to the functionality of the device. Every device, no matter the condition, is in full working order and has been fully checked and tested using industry-level software.