Extra outlets sockets or extensions cord

Check the Carnival FAQ. As I pointed out before, it's usually already there.

I use one similar to his without the cord (OneBeat) all over Europe and on Carnival cruise and my sister used it on RC. It worked like a charm to (3) plug in my hair straightener and (3) USB outlets for phones, iPads, and power banks.

I'm not sure which line you're going on. but in most cases, this question is addressed in their FAQ section.

There are a lot of different styles and shapes. Here's the one we use.

https://www.amazon.com/Essentials-Protector-Outlets-Extension-Accessories/dp/B0BJ1TW7N7/ref=asc_df_B0BJ1TW7N7/?tag=hyprod-20&linkCode=df0&hvadid=647198487738&hvpos=&hvnetw=g&hvrand=13361901319149861173&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9018800&hvtargid=pla-1953785528611&gclid=Cj0KCQjw756lBhDMARIsAEI0AgmpjkZfmktvfn7m18Gaf_HPPtAEnZjmwQh1M-bVKNtGydbhV7eLVf4aAisgEALw_wcB&th=1

I also pack this one because sometime the extension cord is more of a pain

https://www.amazon.com/Outlet-Extender-Multi-Plug-Essentials/dp/B0BHYP9GBQ/ref=asc_df_B0BHYP9GBQ/?tag=hyprod-20&linkCode=df0&hvadid=647221105120&hvpos=&hvnetw=g&hvrand=13361901319149861173&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9018800&hvtargid=pla-1953438475614&psc=1&gclid=Cj0KCQjw756lBhDMARIsAEI0AgnCkApKnhr7JcdLH_zTNWK1uHJOyLILTS8j9OxaoLzPzVZsVTRhnCMaAn1lEALw_wcB

For Carnival you are allowed to bring a non-surge protected extention cord?