Blackstar HTOD1 Pure Valve Overdrive Genuine tube design; operates at 300 Volts for true hot tube dynamics and feel ECC83 (12AX7) Tube offers two cascading tube gain stages to your rig "A-Class" tone control features Gain, Tone and Level controls Emulated speaker output is a new benchmark design for direct recording High integrity bypass for silent switching and driving long cable runs; Power supply is included