MCINTOSH MC-501 (mono block) solid state amplifier. 500 watts per channel. This amplifier was used in my dedicated home theater and ran my center channel. I ultimately upgraded to the MCINTOSH MC-601's to run my L,C, R channels and ended up selling two of the MC-501's to my best friend & one was left over. The one remaining amplifier was put into storage and I never got around to selling it. The amp is in very good condition. I inspected the unit a few weeks ago & could not find much in the way of cosmetic defects. I rated it an 8/10 in the event i missed something. I always try & air on the conservative side. Sonically, the unit functions flawlessly. Overall, you cannot go wrong with this amplifier, it's in great shape & sounds wonderful.