Extremely rare bass!
Something odd in those photos though. It shows red burst on the closeups but the full length photo looks like a solid black body. Even the worst of photos wouldn't conceal the red burst, so I'm thinking at least the full length shot was doctored or touched up for some reason. Maybe the original owner wanted to see what an all black bass would look like and touched it up, forgetting he was going to list it later? I don't know. Too bad those Ampeg basses with only the single "mystery" pickup sound like crap. I had a righty AEB-1 years ago, and it was, hands down, THE worst sounding bass I've ever heard. Zero sustain with the unique sounding plastic-like "boink" tone when you plucked it. Ampeg wised up when they introduced a "real" pickup in the sweet spot later on (AMB-1), but I don't know if the Devil basses ever got that far.
I don't see it (does anyone else?), and the fact that he wouldn't simple tell me the serial # and gave me a snippy answer instead is offputting for me.