Seed beads are uniformly shaped, spheroidal beads ranging in size from under a millimeter to several millimeters. Seed bead is also a generic term for any small bead. Usually rounded in shape, seed beads are most commonly used for loom and off-loom bead weaving. They may be used for simple stringing, or as spacers between other beads in jewelry. Mill Hill Seed Beads are a size 11/0, which has a diameter of 2.5mm. Some colors of these beads are washable, others are only colored with a finish so are not washable.