Strands can be constituted-of-or-filled-with natural fibers.
A strand can be constituted-of-or-filled-with progressivism.
A strand can be constituted-of-or-filled-with optical fiber.
Some strands can be constituted-of-or-filled-with investings.
Strands can be constituted-of-or-filled-with (swarovski crystal).
A strand can be constituted-of-or-filled-with (surface barriers).