50 watt multimedia stereo amplifier with built-in UHF 16 Channel wireless receiver, 3 mic inputs, line in with separate volume & tone controls; line out. For flexibility in presentations up to 4 mics can be used simultaneously: 2 wireless, one dynamic and one condenser with phantom power. The Wireless Multimedia Stereo 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. Power with 10 alkaline D-cell batteries. AC Adapter/Recharger or rechargeable NiCad Battery Pack, also available. 8-1/2"W x 8-1/2"D x 3-1/2"H overall.