Carl Zeiss-Jena manufactured 7x40 DF (porro) and 7x40 EDF (roof) binoculars, both of whom have rubber eyecups that "accordion."
Rather than having to fold the eyecups over themselves to use with spectacles, you merely press the eyecups firmly into your lenses. The eyecups "accordion" within themselves -- compress -- to become, until you relax the pressure, as short as fold-overs.
I have two Zeiss 8x30 B/GA IF Olive binoculars. Will these eyecups fit my ocular housing to replace the ones I use now?
I can't ask Zeiss-Jena; they're OOB. I can't ask Zeiss-USA or Germany; they will neither know nor authorize any non-Zeiss accouterments. And the eyecups are too expensive to buy without reasonable likelihood of a fit.