Dynaco MRK VI rare vintage stereo tube amps (2) Mono Blocks. 2 monster power amps in nice shape. These belonged to a local audiophile and former high end stereo dealer and were his favorites. He ran them with the pictured AR SP3 thru a set of JBL 4311's and it sounds stunning! The have Russian Electo Harmonix 6550's. Everything is as he left it and I do not know any of the units history. I have been playing them all week and if I had a need or room I would hang on to these gems!