A circular object with a central perforation intended to act as a fly wheel on a spindle, giving momentum to its rotation - an artifact providing evidence of the spinning of thread. It would maintain the momentum of the spindle rotated by the spinner while he/she teases more fibers out of a fleece. They may be of stone, bone, or pottery, varying from flat disks to spherical or pyriform, and ranging 2.5-10 cm in diameter.