Eternity rings feature diamonds all around the band. The channel setting means that the gemstones are set on the top and the bottom, with the setting sitting on level with the stones, creating a little 'channel' that the stones sit in.
A bezel - or collet - setting is where the setting metal surrounds the girdle of the gemstone. Learn more about the anatomy of a ring here https://www.acsilver.co.uk/acsnews/2019/05/06/anatomy-of-a-ring/
