Suitable for Singer front-loading sewing machine stainless steel bobbin box Package includes: This product package comes with 4 pieces of high-quality sewing machine bobbin cases, providing you with enough replacements to use for a long time or share with others. Compatibility: These bobbin cases are compatible with many other zigzag sewing machines, making them versatile and useful for various sewing needs. Functionality: The bobbins in these cases can stop spinning more quickly, which effectively prevents unraveling or tangling of the bobbin thread when sewing operations start and stop, making your sewing experience smoother and more efficient. Material: Each bobbin case is made of durable and practical stainless steel material that can withstand long-term use. Easy to use: The sewing machine bobbin case is easy to install and replace, making it a hassle-free solution to keeping your sewing machine running smoothly.