wrote in message
.. .
It is also just possible that the Speed Seal design has been
made
to work with a rubber ring gasket (I don't know them),

Boy I feel dense. Yes, the speed seal cover has an "O" ring in
it.

Hey, don't feel dense. A lot of engineers out there won't be able
to sail like you can. Horses for courses.

This cover sounds like a good design which should have been
adopted by Jabsco - who presumably refused to pay the licence fees
.. . .
--
JimB
http://www.jimbaerselman.f2s.com/
for opinions comparing Greek cruising areas