Fishman PRO-AGX-312 Undersaddle Pickup, Pickups for Acoustic Guitars, For mounting under the bridge, Passive - does not require a battery, Suitable for concert guitar or 12-string guitar - 3.2 mm (1/8"") saddle width and 59 mm (2.31"") E to E string spacing, Includes jack socket with strap pin@+*Note:* The sound quality can be significantly improved by using a pre-amp@+@+