Treatment for portlight gaskets

[skunther]

Does anyone use any product to keep their portlight gaskets fresh and functional?

I know for car door gaskets, wiping down with a silicone spray is recommended. I’m not sure if this is also appropriate for a boat.

 

[Terry Cox]

I've used a silicone gel on ours to keep them pliable and sealed for years. Pool supply stores carry it for pool valve seals. Works great. Application by finger good for several years.

 

[BigEasy]

303 aerospace protectant is good.

 

[Ralph Johnstone]

I've used this for 25 years and all port, hatch, and sundry gaskets still look like new :

Again, a silicone product as above. Even the vinyl rub rail looks like new and it sees whatever sun we have continuously over the years.