Sizing rings. This is a set of sizing rings with a label tab. They range with an inside diameter from 22 to 44mm in 2mm increments. They are for sizing round things and hopefully cover all the sizes that most people have. These are strictly for sizing things and are not meant to be jewelry or decorations. If you measure them with calipers, you might find them off by 0.2-0.3 mm, but they are sufficient for measuring most people's round things.
The author marked this model as their own original creation.