This is a SansAmp Classic, reissued around 2021. Unlike the previous version with a stereo mini-plug, the power supply can be driven by a standard DC9V adapter with a center-negative polarity. Current modifications include: ① Addition of a clean mix knob via SPI, ② Impedance mod by EVA. ③ *The toggle switch in the upper left was installed during another mod, but that mod has now been reverted. Therefore, the toggle switch does not function. Also, the battery cable has been removed due to this, so battery operation is not possible.* Please understand that this is a modified product with modifications ① and ② before purchasing. Operation was confirmed to be problem-free. Includes the main unit, box, and instruction manual. #guitar #bass #effector #preamp #amp #sans #sansamp #ampsimulator #marshall #mesa #fender