Vintage MASON-DIXON LINES Trucking Truck Driver 15yr Safety Award Pin

Description

Vintage MASON-DIXON LINES 15yr Safety Award Pin.
It looks like it has wear in the pictures but the raised areas are shiny on a matte surface.
It's not marked but looks like sterling silver to me.
Comes in the original 1970's? plastic box.
Looks giant in the pictures but it is about the size of a dime.
Please see the pictures for best description.
I have a couple of these if you'd like more than one.