These look like coiled springs - and - they are. Not even soldered - they could be pulled open if you wanted to. Which makes them pretty flexible about the beads that they fit next to.
Metal components from a vintage warehouse sale - these were probably produced as custom items for a well-known fashion jewelry house, and these would be end of line when production changed. Lot of creative possibilities here!
11mm x 6.5mm Inside diameter (ID) is 9 mm. By the pack of 10.