Available for immediate purchase Bass preamp with adjustable treble, bass, and volume. - Model Name: Bass Preamp - Brand Name: Sadowsky Pedals - Functions: Treble, Bass, Volume adjustment - Power: Battery-powered - Included: Original box Thank you for viewing. This is a preamp for bass guitar effects. I used it several times in live performances, but I'm selling it because I no longer use it. It has some signs of use, but it works perfectly.