The classic BOSS SD-1 Super OverDrive guitar effects pedal in its iconic yellow finish. Features three control knobs—LEVEL, TONE, and DRIVE—along with a red CHECK status indicator. Designed to deliver warm, natural overdrive tones for electric guitars. Shows some signs of cosmetic wear from normal use. Original box and accessories are not included. Technical condition: Fully tested and 100% functional, with no history of repairs. Power: 9V battery or BOSS PSA series power adapter (neither is included).