this is abused Boss TU2 tuner pedal. it has served me well, no power supply is supplied but it has input and output jacks so you can daisy chain other pedals off it if you want to. The BOSS TU-2 Chromatic Tuner is a compact pedal tuner made by the renowned brand Boss, known for its high-quality musical equipment. This unit is suitable for various instruments such as acoustic guitars, electric guitars, and bass guitars. Made of durable metal, this tuner is designed in a sleek white colour and originates from Japan. With its reliable performance and easy-to-use features, the BOSS TU-2 Chromatic Tuner is a must-have accessory for musicians looking to keep their instruments in perfect tune.
