What you will receive: The package contains 4 sewing machine bobbin boxes, you can replace them according to your own interests, or share them with others. Application: The bobbin box has been used as a replacement part for the front-loading bobbin system sewing machine, and can also be used as a spare box Function: The bobbin can stop rotating faster, effectively preventing the thread from loosening or tangling when the sewing operation stops and starts Size: Each bobbin box is about 22.75mm in diameter and can be used for most sewing machines, such as Babylock, Bernina, Brother, Elna, Janome, Kenmore, Singer, etc. Material: This bobbin box is made of stainless steel, durable and perfect for long-term use