Medal fixing pins are not subject to any restrictions and are permitted in your carry-on or checked in luggage or on the person [for displaying medals].
There are no restrictions.
This item is not restricted.
You will be asked to relinquish all dangerous or prohibited items found in your carry-on luggage. If you refuse:
We x-ray bags going on planes to make sure there is nothing dangerous in them. If something comes up on the x-ray that needs checking, the bag will be opened, searched and any dangerous or prohibited item will be removed.