Granular Silica Gel is a synthetically modified silicon dioxide that has been purified and processed into a hard, smooth bead. This gel is synthetically modified to give it a vast internal network of interconnecting cavities creating a very large internal surface area for adsorption as a desiccant. Granular Silica Gel has a lower vapour pressure than the air that surrounds it, molecules of water can easily adhere to its surface. Absorption is no longer possible when equal pressure is established. Thus, if the humidity is higher in the air, greater the absorption of water. Since their micro-porous makeup has cavities that are interlocking, the gel has an extremely high area of surface, it makes for a perfect desiccant of high capacity.