K&K Pure Preamp Belt-clip Preamp for K&K and Other Pickups Includes Bass, Midrange, Treble and Volume Controls Works with Pure Western, Pure Classic, Pure Bass, Pure Archtop, etc. Also works with K&K The One, Big Twin, Big Shot, Bass Max, Violinissimo, etc. Add a Preamp to your K&K Pickup Without Modifying your Instrument!