A-grades: Little to no imperfections. These pins truly encompass the original design and show almost no defects. Great for collectors.
B-Grades: Minor imperfections that are only visible upon close inspection. These may include scratches, underfilled or overfilled enamel, and other very minor defects. Also great for collectors if standards are not available.
C-Grades: More noticeable imperfections that are visible upon close inspection. These may include overfilled or underfilled enamel, scratches, black streaks, etc. Great for budgeted buyers.
Seconds: Multiple visible imperfections upon close inspection. May include miscolored enamel, underfilled or overfilled enamel, missing enamel, etc. Usually the worst of the batch and the sold for the cheapest price.