This is from a guitar I purchased used. I have confirmed that it produces sound. It is being sold because it became unnecessary after a pickup replacement by a musical instrument store. Only the main unit, the included screws, and springs are included. [From the site description] DIMARZIO guitar pickup, DLX PLUS Bridge, Black Specifications ■Type: Guitar pickup ■Model: DLX PLUS Bridge, Black ■Output: 400 ■Treble: 6.5 ■Mid: 4.5 ■Bass: 7.0 ■DC Resistance: 17.28kΩ ■Magnet: Ceramic