Based on our understanding of  the Ring found in the tomb of Queen (and general) Fuhao (approxi. 1200 BC).
 
Features of thie ring:
---Great for all kinds of bows. It is a good ring to practice the shallow hook technique or swtiching from a lipped ring to the manchu ring.
---Once you get the technique, it is ideal for heavy draw weight bows.
---Sizing tolerance: a little too big and a little too tight can both work on this ring. If you are not sure about your thumbring size, try this one.
 
 
Please refer to this page to measure.