In the majority of our mixes the beads are all 11/o seed beads. Some combinations may have a size 11 triangle or hex. Linen and Dark Linen come to mind. The tubes hold 27 grams to 30 grams. Tubes with metal 11/o seed beads in the mix will bring the weight up to over 30 grams - hence why the average weight is given. The seed beads are Miyuki Glass Seed Beads. The mixes range from 4 to 6 colors of beads in a mix. Many of the seed beads will coordinate with Glass Garden Bead's Small Bead Mixes. When ordering use the drop down menu to identify the color of the mix.