I had previously posted my impressions of the new Legacy E9s, and mentioned that the bellows-type diaphragms between the units did not quite meet. I was playing with them this morning - I plan to make a 1/4 thick dark gray insert to go between the two units' diaphragms to "seal the deal."
I noticed that these diaphragms are not just cast rubber bellows like on other F and E units I have seen, but two pieces solid plastic pieces. There is a solid, non-moving piece that screws to the back of the unit and a springloaded, swiveling piece that turns. Very nice! Maybe this has been used on other units but I have never seen this.