SINGER Bobbin Pins help organize sewing supplies by pinning matching color thread spools and bobbins together. No more tangled threads or searching through tons of threads to find the right thread colors for a project. Simply pinch the bobbin pin, insert the ends into the bobbin, and slide the bobbin up the bobbin pin until it rests on the groove. Then do the same with the matching color thread spool. Both bobbin and thread spool will stay together for easy organizing. To separate, just pinch bobbin pin and pull. Details: Red, grey and white2.625" x 1.875" (at base opening) x 0.56" (at top ring) (6.67cm x 4.76cm x 1.42cm) Set of 20 Organize bobbins and thread spools so they don't tangle or get lost Keep like thread colors and materials together Pins bobbins to matching thread spools