The Cap Nut is very effective and made using high quality metal. The offered nut sometimes called Acorn Nuts are hex nuts with a finished dome top that covers the exposed end of the bolt. This provides a finished look to the threaded end. This Nut helps prevent stripping of the threads and provide a decorative appearance as a finishing fastener. The Cap Nut is used to cover exposed threaded stud, rod and bolt ends with a dome-like cap.