Collar stays are hidden as they are inserted into the underside of the collar of your dress shirt. As they are out of the way, most people don’t even know of their existence, let alone their function. Collar stays are usually made of metal or plastic and are inserted in the flip side of your shirt collar to keep your shirt collar straight and flat against the collarbone. Collar stays help to keep your dress shirt collar in place for nice and neat appearance.
Collar says are either removable or sewn into your shirt collar. The upside of a sewn in collar stays is you don’t need to remove them when you laundry your dress shirt, which also means there is less chance of misplacing them. However, the downside is when you dry or iron your dress shirt. Plastic collar stay which have been sewn into the collar may melt and lose their shape when put through the drier or when ironed, thereby adversely impacting the appearance of your collar. If you have removable collar stays, make sure you look after them so you can use them again after your dress shirt is cleaned.