Player Mustang® Bass PJ Since its original release in 1964, the Mustang Bass has been one of Fender's most enduring bass designs, finding its way into the hands of bassists ranging from The Rolling Stones to My Chemical Romance. This updated version of the short-scale underground hero adds the power of our venerable P Bass® and J Bass® pickups to the traditional Mustang design for flexible, thunderous bass tone with smooth playing feel and slick visual style.