Dr. Elseys R&R Respiratory Relief Litter is available in two formulas silica gel and this clumping clay. This low dust and hypoallergenic litter helps to control respiratory disease in cats created with a biodegradable formulation free from plant proteins, perfumes, or deodorants. The natural essences in the litter along with the low dust help to reduce stress, which can be an important factor in controlling Feline Respiratory Disease.