"The Sizer" 
This model is our reference tool.
As all our rings are ergonomically shaped, they are oval rather than round. To find the optimum fit, we recommend you order this polymer ring first just give us your estimated size is right for you.
We make this ring using 3d printing, so we can make custom sizes.
If you decide to buy a metal ring after trying this polymer ring, we will refund you the cost of this experimental ring.
So there is no risk of ordering a expencive metal ring that is not exactly your size.
All measurements are inside diameters of the ring.
Since each ring is individually crafted, all custom wishes are possible on request.