CONTINUOUSWAVE

I recently replaced four 1-inch brass through-hull fittings on my Revenge V-22. I want to replace the corroded covers. I cannot seem to find a source.

[Implied question: What is a source for the Perko Clamshell Vents used to cover drain outlets on the hull?]

Any help would be appreciated.

You are probably asking about the PERKO clam shell ventilators that are fastened to the hull to provide a shield for the through-hull drain outlets and help create a Venturi effect. If so, there is information about the PERKO clam shell ventilators in the FAQ Answer to the question:

Q12: How Are Drain Tubes Replaced?
http://continuouswave.com/whaler/reference/FAQ/#Q12

When reading the FAQ you can follow the hyperlinked text "Perko clam shell vent" to the PERKO Website at

https://www.perko.com/catalog/ventilators/241/clam_shell_ventilator/

Read the FAQ to learn how to modify the stock PERKO clamshell vents to use as a shield or cover for the hull drain outlets and to create a Venturi effect to help promote faster draining.

The PERKO Clamshell vents are sold by many marine shops. I am sure you can find a vendor near you that has them. Or contact PERKO to see if there is a distributor or retailer near you. Or order them on-line.

If by "covers" you meant something else, please explain in more details what you are looking for.

The OEM part is a Perko vent clam shell 2"x2" and is chrome plated brass. The part # is PKO-315DP2CHR

Here is one (of many) reputable vendors that sells the item:
https://shop.hamiltonmarine.com/products/vent-clam-shell-2-x-2--chrome-plated-brass-26338.html

Note- Boston Whaler drilled two additional holes, for a total of 5 holes. You can drill the additonal holes yourself. The location of the two holes can be described as "centered on the "E" of the word PERKO in the photo shown above.

West Marine has the same part for $7.00 more than Hamilton.
https://www.westmarine.com/buy/perko--clamshell-vent-9-16-h-x-2-w-x-2-l--199820?recordNum=2