The ports look like Ronstand units as there is an adjusting screw in each hinge, so the top can easily be adjusted.
Maybe a Chinese knock off, as I don't see the usual 4 pins that hold the insect screen frame in place.
The distance between the closed port and the pins allow a storm port to replace the screen if running offshore.
Some used an angled soffit , so when the port was opened after a rain , collected water would not pour in.
Both nice features.