To commemorate the 50th anniversary of the BOSS brand, a special model, the BD-2-B50A, has been released, featuring a metallic painted casing, silver screws, and a commemorative emblem. Amplifier-like circuit design The BD-2 employs a multi-stage clipping circuit design, similar to those used in vacuum tube amplifiers. Furthermore, by using a discrete circuit configuration, we were able to achieve sounds that guitarists adore, such as wild crunch and juicy drive sounds, while suppressing noise. The TONE knob employs a passive circuit that allows you to adjust the high harmonic components. It's also easy to adjust the sound to suit the instrument being used. From crunch to distortion, it produces a clean, well-defined, and beautifully resonant crunch sound for chord strums and arpeggios. As you increase the gain, a pleasant compression is added, giving you a playing feel similar to that of a tube amplifier. Furthermore, by lowering the GAIN and controlling the wide-range LEVEL, it also functions effectively as a full-range booster to push high-gain amplifiers. This overdrive pedal transcends the image suggested by its name, "Blues Driver," and adapts to a wide range of styles.Condition: No problems with use. Parts requiring acknowledgment: None. Accessories: Box, instruction manual. Warranty: No warranty. Sold as is.