The family of kit audio amplifier, 1)6MM Aluminum Alloy Drawing Pannel 2)Compatible With Many Electronics Amplifiers and Vacuum Tubes Factory , Loudspecker2pcsThe base loudspeaker specDiameter 10cm,rated output power 15WThe Treble loudspeaker specDiameter 4.5cm,rated output power 3WFrequency response70H-20KHZ(+/-3dB)Size210mm(L)*140mm(W)*235mm(H) The family of kit audio amplifier