SOPHISTICATED DESIGN: this amp appearance is constructed from high quality stainless steel and solid wood that not only has trendy silver metal texture but also has retro atmosphere.Please download the user manual from:https://s3.amazonaws.com/Doctor-001/GemTune+Amp/GemTune+GS-01.pdf HIGH QUALITY TUBES: We utilize PSVANE brand EL34 tubes for outstanding treble and alto. 6N9P tubes provide deep and powerful bass and we use a 5U4C tube as a rectifier. Our tubes and amp are packaged individually as to avoid damage. GREAT PERFORMANCE: Our Class A single-ended amplifier eliminates any annoying distortion and provides the highest quality sound. Your music will sound great no matter the genre! Our amp perfectly balances tone to give a crisp and clear sound experience.