Line 6 99-021-0716 DT25 25W/10W Guitar Amplifier Head Intuitive, 2-channel design, instantly reconfigurable per channelSelectable operating class (Class AB/25 Watts/Fixed Bias or Class A/10 Watts/Cathode Biased) Selectable power tube mode (Pentode or Triode)Four unique Voicings (negative feedback loop topologies paired with HD preamp and tone stack modeling Bogner design Tube amp