They are hollow silverfill, with an unobtrusive seam on one side.
Great as spacers.
You will receive 30 beads total.
Silver Filled (aka Silverfill, or Silver Filled, Sterling Silverfilled, and several others) is a layer of .925 or better silver which is mechanically bonded to a brass core. It is hundreds of times thicker than silver plating and has the same properties as Sterling Silver.