PieDuo - Crystal Etched Sliperit Full. The PieDuo bead is a 2-hole bead that allows you to create fun and unique geometric art in your beadwork. Use PieDuo beads to create 3 dimensional beading, exterior accents to patterns or design your own shapes. It’s easy to create circles by beading 4 PieDuos together. The PieDuo bead is made out of high-quality Czech glass and measures 6x8mm with a hole size of .8mm. They come in packs of 50.