TMC TIEMCO CERAMIC BOBBIN CURVED- This bobbin was the world's first bobbin to incorporate a ceramic tube. Smooth and will last much longer than conventional, steel bobbins. (The heavy duty version has larger diameter black ceramic tube and suitable for tying hair flies, streamers, and saltwater patterns). The body is covered with non-slip rubber. The curved bobbins are made so the thread feeds directly into the bottom of the tube and doesn’t rub against the side of the tube. Plus, they tend to fit in the tyers hand more comfortably.