1) They did not seal well. They will sometimes leak while at the dock in a slight drizzle. Sailing in heavy seas, they leak profusely.
2) Like a sliding glass door in your house, when open less than half of the width of the frame is open. This offers very little ventilation even in a good breeze.

These high quality ports open fully to provide improved ventilation without leaks. Supplied complete with interior trim and fly screen.

Known Usage. This port was standard equipment on some later models of the boats listed below:
• Catalina 25
• Catalina 27
• Catalina 30
• Catalina 38

Additional Uses:
• Catalina 38: Some owners of the early Sparkman & Stevens design report success using this port to replace the original sliding lens opening ports.
• Catalina 400: A replacement for the original Lewmar Old Standard version the boat was built with.

There may be other instances we are not aware of where Catalina used this port as well. They were not used every year the boat was produced. During some years fixed ports or other opening ports were used.

Port:
• Outside of mounting flange (measured on the outside of the boat): 425mm x 176mm (about 16-3/4" x 6-15/16")
• Port opening: 14" x 4"

Cut out size:
• 405mm x 156mm (about 15-15/16" x 6-1/8")

Please note that these ports are built in England and made to metric system standard dimensions. All Imperial equivalents are approximate.

The size of the cutout required for this port should be a bit larger than the hole in which your existing port is mounted. This will allow you to trim the deck to the proper size opening using a jig saw. Check the dimensions of your port and the opening in your deck before ordering. It is always possible Catalina Yachts or a previous owner has installed a different port than we expect. Let's be sure what you are working with! Lewmar New Standard Size 2