Enamel pins are handmade items that have natural variations and slight flaws that can occur during the production process. As a disclaimer no pin will ever be 100% perfect. Please keep in mind that everyone's grading system is different. I grade my pins by the batch and by its design.
Highest quality pins from batch. (May contain minor imperfections that can only be seen under very close inspection. Speck of dust, stray glitter, uneven enamel, scratch on surface and or tiny bubble in enamel.)
If you wear your pins on a daily these would be great to have. They have the most visible defects.