Anything better than neoprene for protecting your dome port?

[AlClarence]

I have the standard AOI neoprene cover for my 8" dome.  My dive buddies saw some divers rocking a big flexible rubber cap the other day but didn't get any details. Would anyone happen to know what they could have been using? I've been searching but I'm having no luck finding anything

 

Thanks in advance, Al

Edited February 20 by AlClarence

[FrancoisC]

Be aware that neoprene cover can leave some traces on the port if not completely dry.

 

I have made a 3d printed flex cover for my dome port.

The glass is not touching the cover.

But it is a little bit to bulky to keep it with me while diving...

[Chris Ross]

Neoprene has some advantages in that it's easy to leave on the dome while getting in and out of the water and easily clipped off once you are in the water. 

 

It also can serve to keep the dome surface from drying out between dives.  There have been a lot of discussions on this topic with regards to water spots forming on the glass surface.   Water spots occur when salt water is allowed to dry on the dome surface, the salts become more concentrated as the water evaporates and this eventually etches the glass.  If you keep the dome cover on it slows down evaporation considerably until you can soak your housing in fresh water at the end of the day.

 

Unfortunately the standard design of neoprene cover can easily be lost on entry/exit when shore diving I got one of these:

 

https://www.bennimarinedesigns.com/gifts/cameraportcover

 

It seems to fit the port well but not tightly covering the surface, haven't tried it wet as yet but seems to be well made.