Russian guitar usually differs from the wood in the rest of the neck. The neck joint or heel is the point at which the neck is attached to the body of the guitar. The fingerboard is made of hardwood (ebony or rosewood are common), fitted with metal frets of brass or steel. Fret spacing almost always follows the western twelve tone equal temperament (12-tet) system. The surface of the fingerboard may be flat or curved slightly ("radiused"), although the curve on the Russian guitar is usually somewhat less than that of an equivalent western 6-string guitar. Inlayed position markers are common, and
Rhythm game accessories existing "Rock Band 2" drum sets. For the pro guitar mode of "Rock Band 3", a pro guitar controller is required. Unlike standard guitar controllers, pro guitars allow input of any fret/string combination, allowing accurate simulation of a real guitar. The Fender Mustang Pro Guitar controller, which is based on the Fender Mustang, has 102 buttons along its neck which simulate holding the guitar strings against the fretboard. All six strings are represented along 17 different frets. In order to simulate picking/strumming, the Mustang pro controller features a "string box" located on the body of the controller (around the position