Vintage 90"s Jensen Mosfet 100Wx4 Amplifier A4320. It works well. It has some discoloration as pictured. Other than that it has normal cosmetic wear. RMS Power 50x4 at 4 ohms, 50x2 plus 125W in 3ch mode or 125x2 at 4 ohms bridged. Measures about 17"x 9.5".