Little House Pincushion Ring
Adjustable Pincushion Ring made in Japan by Little House notions.
If you are wondering why to wear a pincushion on your finger, there's an answer for that!
If you are mending, and removing pins as you stitch, it can be more convenient to poke spare pins into a pincushion attached to your finger for safe keeping.
It can also be helpful when embroidering to poke the pin into the pincushion while you prep a new thread.