Xvive TremoloPedal True Stereo - Undulator V16 The Stereo Undulator is 9-voltage supply pedals but with a higher headroom less distortion and improved clarity. The Stereo Undulator is a wide range of effects. It would give the sine wave modulation at one end , the trapezoid modulation wave at the center and the square wave modulation at the other end. All analog signal path for a warm and rich tremolo effect. Dual ouput channels, stereo output and mono ouput , for a variety of setup options. 2 pcs guitar picks as gift.