This ELAN shank button is made for garments and accessories where extra thread clearance helps on thicker layers. It measures 11 mm (3/8") in diameter and includes 4 button(s) carded for replacements or coordinated use. Sew it on by hand through the shank with strong thread, and check placement so the closure lies neatly without pulling; test on a scrap to confirm needle size and stitch length, match thread weight to the fabric for a clean finish.