Why Pre-Owned?

Second hand doesn't mean second rate functionality.
 

All of devices undergo an extensive quality control check and is guaranteed to be 100% functional regardless of its grading, unless this has been specified in the description. 
The cosmetic grading relates only to the device's overall physical appearance.
 

Cosmetic Condition Explained:

Best - Like new:
Like new or "near mint" condition.
 
Better - Lightly used:
The device may show signs of character, meaning there may be some light cosmetic scratches and scuff marks on the case.
 
Good - Slightly More wear & tear:
There are more evident signs of wear on the case. These may include small knicks and more visible evidence of scratches.