shank

A shank is a device for providing a small amount of space in between a garment and a button. Shanks are necessary to provide space for fabric to sit in between the button and the garment when the garment is buttoned. Shanks also allow a garment to hang and drape nicely. Types of shanks There are two types of shanks: Button shank Shank buttons have a hollow protrusion on the back through which thread is sewn to attach the button. Button shanks may be a separate piece added to the back of a button, or be carved or moulded directly onto the back of the button, in which case the button is referred to by collectors as having a 'self-shank'. This is a common construction for older shell and glass buttons, for example. Buttons with shanks have no holes in the button blank (the main part of the button) itself because they are not needed for sewing. Buttons with shanks are more expensive to produce than shankless buttons. Thread shank