I recently made an offer on this objective on eBay because it was already fairly cheap, and I could tell it had a longer-than-45mm parfocal length, meaning it was likely a relatively newer design. Objectives are often shucked for incorporation into third party equipment, either to fit better or remove brand ID or both, and sometimes that means you're getting something really good for a fraction of what it would cost.
I just got it in and tested it by handholding it onto my nosepiece (no threads), and it's definitely not meant for a Nikon infinity system anyway. Top to bottom it's about 65mm, suggesting maybe a 60mm parfocal length if the threads went over the grey bit at the top? It has about 1mm or so of working distance, and gave about 160x or so magnification on my 200mm tube lens, along with extremely strong red and green axial CA and fringing. It reminded me of what my Zeiss planapo smartzoom 1.6x objective looks like when put onto a non-correcting system. The pictures I took with my phone while handholding it are probably not really useful, just enough to get a sense of the magnfiication. I was using coaxial illumination, and tried it both with and without a cover slip--without actually seemed a bit better.
Anyway, it is a curious mix of features. My guess is it's one of those low-res, high-mag industrial objectives, maybe by Zeiss or Leica/Vistec? But I am not sure if they ever made them with longer parfocal lengths.
Edit: did some googling in case it really was a 150x objective, and it looks like Reichert had 60mm parfocal objectives, and by golly one of their lwd 150x plan apo objectives looks similar on the front. So...maybe that?
Have questions about the equipment used for macro- or micro- photography? Post those questions in this forum.