Nikon 50mm int mount rear cap for Zunow 5cm 1.1?

[davidriver]

The original Nippon Kogaku plastic rear caps for internal mount 50mm lenses that the head bartender selling here at the bottom of the page:
http://cameraquest.com/frames/nrf_for_sale.htm

Will that fit a Zunow 5cm f1.1? Your input is sincerely appreciated!

Dave