Furnished content.
(from Lumberjocks.com)
These are actually just test or practice pieces … the two were constructed out of a single set of 3/4” rings, split in half on the bandsaw. Each is about 2-3/4” high and 3-1/2” in diameter. The rings are 50/50 maple and black walnut.The jig is based on one by ThePapa1947 ... here's a link to his YouTube video on the jig.