We are manufacturer, professional amplifier 1, 60W*4 100W*4 150W*4 200W*4 2, 4 channel outputs 3, 70/100V, 4-16ohm ... output with 70V,100V outputs. LED level indicator.2. 6 channel outputs, individual volume control for each channel3. Chime& Mute function4 ... for each input.5. Short-circuit. over-load protection. 4 channel power Amplifier