how to set mesh render as double sided?

hello,
I did a simple search on the forum and cant find what i want…
I dunno if anyone else asked the same question before

my object looks good from outside, but if look from inside out, the face was culled, is there any settings/script to make it visible from both inside and outside?

Yes, it has been asked before. :wink: Normally it’s best to model with two actual sides.

–Eric

thank you for your help very much