One problem I’ve had as a big man who wears shirts and ties often is that my collars as they age tend to “roll” around my (let’s call it a) neck. The place where the collar is attached to the shirt fabric pushes down so you can see the inner portion of the collar. This drives me nuts!
Cue Wingman!
These are new collar stays that extend back under the collar. If you AREN’T wearing a tie, it keeps the collar straight and in form so you can wear non button down collars casually. If you ARE wearing a tie though, it solves my problem above. It makes old shirts looks and act like new.  
Can’t say enough about them but highly suggest them to everyone looking for collar stays!
https://wingmanhq.co/

https://www.instagram.com/wingmanhq/