For sale is an incredibly rare vintage RCA OP5 Portable Broadcast Amplifier model MI-4223-A. From the same lineage as the OP6 and OP7. This one just got back from full servicing and is fully functional. It will include all the needed XLR in/out cabling for operation. Includes custom built power supply. These hardly ever show up for sale, if you have been looking for one of these now is your chance!