A P.A.F., or simply PAF, is an early model of the humbucker guitar pickup invented by Seth Lover in 1955, so named for the "Patent Applied For" decal placed on the baseplate of each pickup. Gibson used the PAF on guitars from late 1956 until late 1962, long after the patent was granted. They were replaced by the Patent Number pickup, essentially a refined version of the PAF. These were in turn replaced by "T-Top" humbuckers in 1967, and production ended in 1975. Though it was not the first humbucking pickup ever, it was the first to gain widespread use, as the PAF's hum-free signal, tonal clarity, and touch sensitivity when paired with higher-gain amplifiers made the pickups popular with rock and blues guitarists. The PAF is an essential tonal characteristic of the now-famous 1957–1960 Gibson Les Paul Standard guitars, and pickups of this type have gained a large following.

A humbucker, humbucking pickup, or double coil, is a guitar pickup that uses two wire coils to cancel out noisy interference from coil pickups. Humbucking coils are also used in dynamic microphones to cancel electromagnetic hum. Humbuckers are one of two main types of guitar pickups. The other is single coil.