Contents: 4 pieces spool pin cap set Compatibility: Designed to fit a wide range of sewing machine models, with seamless compatibility for models including 4423, 4432, 4452, and many more Material and appearance: Made from sturdy plastic in white, built to withstand regular use while securely holding your spool thread in place Function and performance: Helps secure thread unwinding and prevents tangles, enabling smooth thread flow during sewing and reducing interruptions Use scenarios: Replacing worn spool caps during routine sewing tasks to maintain consistent thread flow Quilting projects where reliable thread unwinding is important Garment or alterations, or for beginners and experienced sewers who want a dependable spare cap set Benefits summary: Aligns with multiple models, durable white plastic construction, reduces tangles and interruptions, supports smooth unwinding for better sewing results