Electric guitar from signature series - John Mayer. The PRS Silver Sky is the result of a close collaboration between Grammy Award-winning musician John Mayer and Paul Reed Smith. Some of the more distinctive specifications include, the headstock shape, tuners, neck and fretboard, bridge, and pickups and electronics. The headstock shape is based on PRS’s trademark design, but inverted to both accommodate Mayer’s playing style and also to keep a consistent length of string behind the nut, which makes staying in tune easier. The tuners are a traditional vintage-style, closed-back tuner, but with PRS’s locking design. The neck shape was modeled after 1963/1964 vintage instruments, and the fretboard has a 184 mm radius. The 635JM single-coil pickups are very round and full, with a musical high end that is never “ice-picky” or brash.