Good morning folk's.
I was wanting to know the proper humidity level/setting for a gun safe. I just got my custom built safe delivered this morning

I want to set the humidistat to the best possible Correct setting. I have some pretty old collectors items. And I would hate to screw any of the wood, or steel up by an incorrect humidity setting.
Any help with this matter would be greatly appreciated !
thank's in advance.
and have a good and safe day everybody.