This is a vintage 1978 BOSS Chorus Ensemble “CE-1” electric guitar effects pedal. This particular example, serial number 215608, is in excellent all original condition. Features of this unit include Vibrato, controlled via speed and depth while the chorus utilizes just one overall effect level knob. This may sound limiting but it’s quite the opposite. Through its range, this single control offers everything from subtle shimmering chorus to near Leslie cabinet simulations while never losing an ounce of its musical quality. Of the 2 foot switches one selects chorus or vibrato and the other turns the selected effect on or off, but the secret to those magic CE-1 tones lies in careful use of the gain control. This clever feature means you can optimize the input level to suit any type of guitar ranging from a low output strat to a beefed up Les Paul.