SPECIFICATION Model Keyboard Amplifier K-250 Speaker Driver LF:1x15 Inch ;HF: 1x3 Inch SpeakerImpedance 4 Ohms RMS Power 250W;400 W(Peak) Input Impedance 220 Kohm Input Sensitivity 250mV(1KHz) S/N 76dB Frequency 45Hz~3.2KHz Power Supply AC 110V~240V;50Hz~60Hz Material 18mm Particleboard;PVC or Cover cotton Main Color Black Features (1)1/4Inch High-Z Input;(2)Level Control, Gain ;(3)FX Send& Return Jacks;(4)Four Band Graphic EQ ;(5)Reverb Send Control;(6)Gain Switch;(7)Master Reverb&Master Level;(8)Ch.2 Mute Footswitch;(9) Reverb Mute Footswitch;(10)Power Amplifier In/Preamplifier Out;(11) Line Output. Size 67x41x73cm