Brand new lamp in process and, real soon, production: Yes, that's a plunger base! Unused of course. I had been planning on using wooden handles of basic plungers for legs on an occasional table I've been working on, and didn't know what to do with the rubber plunger parts. One thought was to use it for the bent lamp base, but the opening is too large. My gal, Jenny B, suggested we just put the fixture/bulb directly on it, no rod. Voila, neat and simple, and wicked cool. Can mount on the wall as a sconce (shown with chrome top bulb) or as a table lamp. Have a few kinks to work out yet, but hope to have it perfected soon.