A fret dress is a basic one-piece number with a plunging neckline, equally at home for fine dining or a casual night out on the town!
Joking aside, a fret dress is a process of leveling frets with some type of flat, straight abrasive surface in order to eliminate string buzzing. When frets become worn, they actually tend to splay outward rather than wear away, which means that they tend to look worse than they actually are. In most cases a fret dress can solve buzz problems without re-fretting the guitar.
To describe the process, first, make sure the neck is straight as possible, then a file or woodworkers’ level with sandpaper attached to it may used to sand down the tops of the frets, taking only the minimum amount needed to make all fret tops the same height. The frets are re-crowned using a fret crowning file and then polished to a mirror-smooth surface. New guitars can benefit from a fret dress, as some may have uneven frets. Gibson used Plek, a computer-based fret-dressing system invented by a company of the same name. A fret dress can also be used to correct minor defects in a guitar neck that might otherwise be prohibitively expensive to repair.