The Gibraltar tailpiece is used to retain the guitar strings on a number of hard-tail Ibanez models. It was designed by Ibanez and produced for Ibanez by Gotoh. It is also known as the Quik Change tailpiece.
The Gibraltar tailpiece is a stop tailpiece which is attached to the guitar body a pair of hex nuts to a pair of studs mounted directly into the top. It serves to retain the strings at the bridge end. Ball end strings can be quickly fed into the tailpiece and once attached to the tuning machine are held securely by the ball. The height of the mounting posts is adjustable.
The Gibraltar tailpiece relies on a separate bridge which allows the string height and intonation to be adjusted. It is often (though not exclusively) used in conjunction with a Gibraltar Tune-O-Matic style bridge. It also was often used in conjunction with a decorative triangular shaped ornament.
The Quik Change II replaced the Gibraltar tailpiece in 1983.
Guitar models equipped with a Gibraltar tailpiece include various Artist series models and Artist derivatives as well as a handful of others. For a full list of models using the Gibraltar tailpiece, see here.