Oddly in 2012 I replaced the lenses in some size1RE ports strictly for cosmetic reasons, scratched etc. Included was a new hardware set for the hinges and latches which are bolted to the frame. This made them difficult to close even on the original compressed gaskets, and it's still a "two handed" job. I think I recall the hinge pin being a different size making the 2 hardware sets and lens incompatible. The gaskets are original from 2001, pretty sure new ones would make them impossible to close but they sure don't leak. Don't know the answer but that hardware change always seemed curious to me.