I've never seen one like this till now. This back has no shutter. The film wind is silky smooth. Could be adapted to fit just about any 4x5 camera with a little effort. It was apparently made as an alternate back for a Polaroid microscope setup. It could be an interesting pinhole camera with a little work. Or whatever you want it to be.
$75.00 with free shipping in the US. A USPS money order is the preferred payment.
Please PM me if you would like this fairly unique piece of history.