The Stromberg Carlson AU-58 - a great sounding head for guitar. Original Stromberg Carlson Tube Set. The AC main cable has been replaced.. sounds really good onb Harp or Guitar. Original Stromberg Carlson tubes. condition is OK and to be expected for its age. There’s a serial number etched on the top of it, which seems to be common for these. sounds great connected to a couple of 12 inch speakers and my Strat . Let me know if you have any questions. Made in the United States