What is the tile's quality grade?

WHAT IS THE QUALITY GRADE?

The quality grade represents another parameter featuring a porcelain tiles supply.

Only the 1st/top quality is characterized by specific regulations. For example, no more than five tiles out of a hundred may present appearance defects. The other quality grades (the second, the third, commercial, kiln output, etc) are of lower quality and may contain a greater number of defects.