Letting this one go after owning her for over 10 years. This is the earliest (and best) incarnation of the 610 preamp (serial number 170).
It has a much beefier more robust toroidal power transformer/supply than the 2-610 & Solo and more eq options than the solo 610 which I actually found very useful on acoustic guitars and vocals. Incredible as a bass DI and on lead vocals to fatten things up. I even love it on acoustics. These are getting more and more rare and this one is in exceptional condition with only a couple small marks on the top from being in the rack. The item "Rare Early Universal Audio M610 Tube Preamplifier Preamp UA EXC Clean" is in sale since Thursday, February 7, 2019.This item is in the category "Musical Instruments & Gear\Pro Audio Equipment\Preamps & Channel Strips". The seller is "christiegilso_0" and is located in Providence, Rhode Island. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Uruguay.