Dry Earth™ is made from a natural stone, we use this substance in the form of a disk at the base of your favorite bathroom essentials. Used to absorb excess water and prevent mold, this anti-bacterial powerhouse is a real game-changer in the bathroom. Replacement absorbent disks for Keep it Clean. - Made of 80-90% natural silica. - Absorbs excess water and keeps odors and mold from forming. - Toothbrush Holder Disk: 2.46" x 0.95" | 6.25cm x 2.4cm - Full Circle Dry Earth disks can be hand washed in warm to hot water and allowed to air dry. - Replace every 6 months as needed.