Lee, there may be more to this part of the story. Wonder if you could take a look? Several months back a couple folks got asking about putting NL eye cups onto an EL, to see if the 6 stops and a more positive click helped those. Swaro NA, do to the Virus and working from home, had not experimented with this and did not know. They sent a set and asked for a report. They threaded on just fine and indeed had the 6 positions with improved feel/clicks. However, in the down position, that inner AL ring did not touch the edge of the lens mount and seemed to create something less than a decent seal from debris between cup and lens, when installed on the EL. With the EL eyecups, installed on the EL, that ring sits down right against, or at least close to the edge of the lens/mount. Since I don't own an NL, I assumed that ring would sit against the edge of the lens when installed on an NL. The NL pic above, with eyecups obviously screwed all the way down appears to have that same gap, note the shadow between the AL ring and lens. If so, then the idea the fit has something to do with sealing out larger debris seems less so. Or, there's another issue with the eyecups? Looking at your sample, with eyecups all the way down does that ring sit above the lens edge or right against it? Tanks