Outer Vinyl Sleeves, is it a good idea?

Mold?
Perhaps it’s from moisture build up from excess perspiration caused by the dancing audiophile 😉

Is he dancing in the nude ?

Speaking of inner sleeves, Mo-Fi inner/outer sleeves are back-ordered at most online vendors. So I decided to try Hudson Hi-Fi Anti-Static Vinyl Record Inner Sleeves (250 pack for $49.95). And they are just as good as Mo-Fi and cheaper which means I’m done with MoFi inner sleeves. 

Spent the weekend adding outer sleeves to all my gatefold albums. These 3 mil sleeves feel great — sturdy, clear, and no more worries about fingerprints. And the price was right too!

https://a.co/d/2BI2qV8

I don't use outer sleeves.