This is something that allows you to adjust the width of a ring by inserting plastic when the ring is too large. Since it's plastic, I feel like it might have a slight yellowish tint due to aging, but it seems to be fine for use. I am probably only using the 3.5mm ones, so they are not included in the product. *Other sizes are unused. If you purchase other items, and if the thickness and size are okay and can be packed together, I can include them for free. Thank you!