Long story short. Opened up surplus desiccant pack that had gotten wet. Looked like bentonite clay inside. Cat litter and small cloth bag is all they are?

I wonder if the composition is a little more complicated though.
I use a brand called "Evadry". The ones I got have a built in heater, just plug them in and in 10 hours or so they have dried themselves out. I have 2 of them that I rotate monthly.

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