Portable 50-watt multimedia stereo amplifier with 3 mic inputs, line in with separate volume and tone controls; line out. The Amplifier works with most microphones including condenser dynamic and wireless. The condenser (electret) input includes phantom power. All 3 mic inputs can be used simultaneously. Tape record your mixed multimedia presentation as it is happening or provide a mixed output to the room's built-in sound system that you control. Connect (with optional Y-jacks) up to four speakers. Power with Optional AC adapter or power up to 200 hours with 10 D-cell alkaline batteries (not included); or Rechargeable NiCad Battery Pack (requires AC adapter).