The Critter and Guitari Septavox synthesizer has 41 keys, 7 modes, 7 tones. One button selects the synth mode, and one button selects the tone. Each button has a LED indicating the setting. With the seven modes and seven tones there are 49 possible sound settings, each one easily remembered as two color combinations: red and yellow, blue and white, and so on: All metal (aluminum) powder coated enclosure: 18.875″ x 3.5″ x 2.125″ (length, width, height (including knobs) Available colors: Matte Black enclosure, yellow knobs with black pointers; Yellow enclosure, black knobs with yellow pointers Weight: 2.0 lbs. (without batteries) 3W speaker (3″ diameter) 41 keys (~3.5 octaves) 1/4″ monophonic output jack MIDI In & Out Jacks Four control knobs: Parameter Knob 1, Parameter Knob 1, Tuning, Volume Seven Modes (LED indicates mode): Vibrato, Slide, Two-Octave Arpeggiator, Swell, Octave Cascade, Slicer, Pipe Glide Seven Tones (LED indicates tone): Dirty Sine, Sine, Electric Organ, Square Wave, Sawtooth, Dirty Square, Computer Power: Ships with power supply: 9VDC, 1.0 Amps, center-positive polarity tip Can also be powered from 4 ‘AA’ batteries Manufactured in USA Includes 1 year limited warranty