The brown silica gel  is a particularly valuable product as it is equipped with a chromatic indicator that allows the product to signal the change of state from dry and new (amber yellow) to wet and exhausted (light blue). It has a standard granulometry variable between 3 and 6 mm. The color indicators are made of harmless substances (cobalt free) and the product is DMF free. The silicagel brown is in granules and is particularly suitable for all industrial applications where the product must be inserted in filters or air or gas circulation systems in general, as the relatively wide interstices present between the material allow better circulation of air.