Tiemco Heavy Duty Ceramic BobbinTheTiemco Heavy Duty Ceramic Bobbin is the first bobbin that uses a ceramic tube and only bobbin uses Japanese high quality ceramic tube. This tubing ensures smooth winding of thread for years of use. The ceramic tube also offers the benefit of lasting many times more than conventional steel bobbin. The bobbin is covered with non-slip rubber tube. This bobbin also offers premium winding when tying thread over your knot when making your own assist hooks.