Wonder Button, Collar Expanders, Collar Extender adds up to 1/2 size to any shirt. They really work! Wonder Buttons, Collar Extenders, Collar Expander, known by many names, are an excellent way to resolve that problem of your shirt collar being too tight. The exclusive Wonder button is a small with nylon strength guard inside a stainless steel spring loop. Made to last. Sold in Department stores for up to $5.00. For a larger view of this item, please click on the picture. Wonder Buttons will add comfort to your wardrobe. Consider getting several.