You add one by adding one.
Follow the arrows. Open up your insert menu, find attachment, insert it into the handle, rename it to HatAttachment, position it as you like, done. From there all you need to do is parent it to the character, ideally not with a LocalScript if you’re hoping for it to replicate.
@.above Should never be using a LocalScript for this use case anyway. OP already seems to be using that code in their original attempt but there’s no need for code to resolve this problem.