I currently have a supply of sealed Dri-Can reusable desiccant canisters for sale. These have never been used and are sealed in their factory air-tight packaging.
These are excellent for ammo storage, gun safes, gun cases, electronics storage, etc.
I have both the Plastic and Metal canisters shown in the below picture. They are filled with indicating Silica gel. When the desiccant turns pink, it indicates that a saturation point has been reached. Regeneration can be achieved by conventional or microwave oven.
Approximate size is 2.25"x4.25"x5/8"
$10.00 ea shipped or 10 for $90.00 shipped