Like new! Behringer VP1 Vintage Phase Shifter. All the Phase 90 tones at a fraction of the cost. The "Tone" switch toggles the internal feedback loop's phase polarity, which changes the overall intensity:

• Down Position (Negative Feedback): Inverts the fed-back signal, producing a smoother, subtler, and more traditional "swooshing" phaser sound with a flat, natural EQ response.
• Up Position (Positive Feedback): Keeps the signal non-inverted, creating a hollower, more pronounced, and "detuned" sweep with sharper resonance peaks (similar to a classic Electro-Harmonix Small Stone phaser set to "Color" mode).