Unleash the full potential of your Singer Heavy Duty sewing machine with our precision-fit accessories! Perfectly compatible with models 44S, 4411, 4423, 4452, 5511, 5523, and 5532, these high-quality add-ons ensure seamless stitching and superior performance. Elevate your sewing projects with ease and efficiency. Sew smart, sew strong, sew Singer! ==== FEATURES: ==== (A) **Universal Compatibility**: These brand new plastic bobbins are meticulously designed to fit a wide range of Singer sewing machines, including the Heavy Duty 44S, 4411, 4423, 4452, 5511, 5523, and 5532 models. But that's not all! They also seamlessly integrate with most home sewing machines equipped with an oscillating sewing hook (shuttle hook). Say goodbye to the hassle of finding the right bobbin and hello to effortless sewing sessions! (B) **Durable Lightweight**: Crafted from high-quality plastic, these bobbins are both lightweight and incredibly durable. They are built to withstand the rigors of heavy-duty sewing projects while ensuring smooth and consistent thread delivery. Whether you're working on a delicate fabric or a robust material, these bobbins will keep your stitches perfect and your sewing machine running smoothly. (C) **Enhanced Sewing Experience**: Elevate your sewing game with bobbins that promise precision and reliability. The clear plastic design allows you to easily monitor your thread supply, preventing unexpected run-outs and ensuring uninterrupted creativity. Perfect for both beginners and seasoned sewists, these bobbins are your trusty companions for all your sewing adventures.