Nok-Out Odor Remover and Disinfectant Hypoallergenic, non-toxic, bio-degradable, odor-free Nok-Out deodorizes and sanitizes. Attacks and eliminates the source of the odor by oxidation, without chemicals or contaminates. removes odor caused by pets, urine, mold mildew and tobacco smoke. Works on carpets, upholstery and other fabrics. Add to the wash or spray in the litter box. For best effects it should come into direct contact with the odor source. When using for disinfectant purposes, apply and allow to remain wet for approx. 10 minutes. Wipe surface with a damp cloth or air dry.