The Superior Electric 6180-PI10 is a indexing controller designed to drive two-phase stepper motors.  It is a two-phase line-operated chopper drive using power MOSFET semiconductors.  Two units are available for sale each, and each is shown in the photos.  Each unit powers up without fault. No further testing performed.  Sold in quantities of 1.

• Model: Slo-Syn 6180-PI10
  
• Serial Numbers: 03692, 01539
• Resolution: 1/10 microstep resolution, als supports full/half, 1/10, 1/125 stepping
• Maximum Speed: Up to 10,000 full steps / second