11mm Tri Beads Opaque White 1000 Pieces. Tri beads are known for their characteristic shape with three arms which allow them to interlock when strung together. The tri bead crafts are 11mm with a 2mm hole. Tri Beads are also known as propeller beads or cartwheel beads.They come in many colors in opaque (solid), transparent (clear), and metallic. Tri-beads are made from plastic which makes them an affordable craft for jewelry projects including ornaments, keychains and bracelets. Around Christmas time many people use tri-beads to make Christmas Tree Ornaments. We sell tons of tri beads in red, green, white, black and clear around the holiday.