Pro’s Choice OSR (Odor and Stain Remover) destroys offensive odors through the natural strength of oxygen and the biological power of odor modifiers. No strong or artificial fragrances are left behind – just clean, fresh-smelling carpet and hard surfaces. Pro’s Choice OSR permanently removes pet odor contamination from stain-resistant carpet. In fact, you get guaranteed results from a single treatment! This non-allergenic products works in just 30 minutes.