Before I found the cold light head, I did a lot of searching and was discouraged on the possible cost for one on places like "the bay". Also, it seemed that some of the cold light heads out there need 208 volts. I was even looking at trying out one of my UV light boxes that I use for Platinum printing to see if it would work. I figured that if I kept the gound glass back on the camera, it might work. That is why the vertical panel unit between the cold light head and the camera back is as large as it is. I built the panel unit, but before I tried it out with the UV light box, I was offered the cold light head at a reasonable price.