Nikkor W 135mm f5.6 lens cap?

[Robert Glieden]

I picked-up this lens used and need a cap for the rear element. Anyone know the size of the rear element?

Thanks,

Rob

[Peter Lewitt]

Mine, in a black Copal shutter(52mm front filter thread, 54mm front cap), takes a 42mm rear cap.

[Robert Glieden]

Much appreciated.
Thanks,
Rob