Official replacement DC power supply for Pro-Ject preamps. Fits the following units: Pre Box S Pre Box DS Head Box S Head Box S USB Dock Box S Fi DAC Box DS (until S/N# D9268) Phono Box Phono Box USB Phono Box USB V Phono Box S Phono Box DS Phono Box DS+ Speed Box S Pre Box RS (until S/N# D16272)