This port design was a replacement for the earlier (and more expensive) 3000 series used on some early Catalinas. This port (like most) has a simple plexiglas lens that seals against the gasket. The 3000 series design had an aluminum frame surrounding and attached to the lens.

Port:
• Outside of mounting flange (measured on the outside of the boat): 17-5/8" x 7-5/8"
• Cut out size: 16-7/8" x 6-3/4"

Known Usage:
• Catalina 25
• Capri 26
• Catalina 27
• Catalina 270
• Catalina 28
• Catalina 30
• Catalina 36

There may be other uses we are not aware of. They were also not used every year the boat was produced.Bomar Series 5000