Bomar has discontinued this gasket. See possible replacement port in "May we also suggest" below.
This gasket fits newer 7-1/2" x 17-1/2" (exterior frame size) opening port.
This port design is one of two that have a unique characteristic. Only one of the two have a replaceable gasket.
While most ports have a simple Plexiglas lens that seals against the gasket, this design has an aluminum frame surrounding and attached to the lens. You can clearly see the aluminum frame in the photo above. The dogs on this series port are mounted on the frame, not the lens and the frame has one seam.
To determine if yours has a replaceable gasket: Look at the frame surrounding the lens from the inside of the boat. If your port has only one seam located at the top of the frame, your gasket is replaceable.
If your frame has two seams (as indicated by the arrows above) the gasket is not replaceable. If you have a leaking gasket, the only option is to replace the entire port. Click on the photo below "Additional Images" to see additional detail. But before you do, please sit down. They are ridiculously expensive. I'd hate to have you hurt yourself in a fall after having fainted!
The factory primarily used Lewmar ports. It is likely various models of Bomar ports were used to continue boat production during periods when the Lewmar ports were not available.
• Outside of mounting flange (measured on the outside of the boat): 17-1/2" x 7-1/2"
• Cut out size: 16-3/4 x 6-3/4"
• Catalina 25
• Capri 26
• Catalina 27
• Catalina 270
• Catalina 28
• Catalina 30
There may be other uses we are not aware of. They were also not used every year the boat was produced.
If you have a different size boat that used this port, let us know and we'll add your boat size to the list to aid other Catalina owners. Bomar Series 3000