2-Hole Halo Beads. Have fun discovering a whole new world of beading design with these 2-Hole Halo beads. Produced by PotomacBeads, the Halo bead is made with high quality Zamak for a durability that will last. The metal rings are designed to quickly and easily bezel around RounTrios, DiscDuos, 2 hole Cabochons and a variety of other 2-hole 6mm beads. You can also use these Halos as spacers for a unique look in your jewelry design. Potomax Halo Beads measure 6.5x3.5mm with a 6.2mm center and come in a pack of 10 and pack of 50.