Bobbin Work: These metal bobbins can be a good helper for your sewing, embroidery, crafting and clothes repairing. Tangle-Free: The practical bobbin case and sewing machine bobbin effectively prevent the bobbin thread from fraying or tangling while sewing. Bobbin Size: Our sewing bobbin cases are approx. 2.1cm/0.82in in diameter, each bobbin is approx. 2.1cm/0.82in. Diameter 2cm/0.8in. Exquisite Workmanship: Designed with polished and smooth surface, the bobbin will not cause scratches. Their edges are very smooth and will not break the thread or hurt your fingers or skin. Compatible: The metal bobbin set is compatible with most sewing machines, such as Baby-lock, Bernina, Brother, El-na, Ja-nome, Ken-more, Sing-er, etc.