The Stop tailpiece is a name for a basic part used to retain the guitar strings on a number of hard-tail Ibanez models.
The Stop tailpiece is attached to the guitar body with a pair of studs mounted directly into the top of the body (or center block for semi-hollow guitars). It serves to retain the strings at the bridge end. Ball end strings can be fed through the tailpiece and once attached to the tuning machine are held securely by the ball. The height of the mounting posts is adjustable.
The Stop tailpiece is most often used in conjunction with a Tune-O-Matic style bridge.
In addition to being the general name for this type of part, this is also the name used by Ibanez to identify a particular tailpiece. This stop tailpiece was used on more affordable instruments instead of the Gibraltar tailpiece or Quik Change II, both of which have slots into which the string can be laid eliminating the need to thread it through the tailpiece.