We often have the habit of throwing away a desiccant bag when buying a new product, but it can help save if your item is accidentally wet or moldy.
Desiccant bags contain small spherical silicon dioxide particles.
According to IFL Science, hygroscopic bags contain tiny spherical silicon dioxide particles that can absorb moisture from the surrounding environment by allowing water molecules to stick to their surface during absorption. Thereby, they help protect other objects from dampness and prevent mold growth.
Some uses of an anti-mildew desiccant bag in a gym bag, save the phone soaked in water or leave the car windshield to avoid fog on the mirror.