I make these bracelets from 8g (3mm) sterling silver wire and copper wire that I put through my patterned rolling mill to give it a snake like pattern.
Afterwards I cut them up in the right length and solder them shut. I then form then on a mandrel and afterwards I oxidize them and polish them to bring out the pattern.
You can choose to buy these alone or in different sets. They come in three sizes: Small -inner diameter 59-60mm
Medium -inner diameter 62-63mm
Large -inner diameter 64-65mm