1965-69 Mustang Weatherstrip Fasteners - Black Plastic(Set Of 4). These are the plugs located at each end of the door weatherstrip, and  hold the ends of the weatherstrip in place. Requires 2 per side on door weatherstripping and 2 per side on the Fastback Roof Rail Weatherstrip. You would need 2 packs of the fasteners  if you need to do both the door and roof rail weatherstripping. Sold as a set of 4.