Simple Solution - Dog Stain & Odour Remover - 4LSafely eradicates dog stains and odours from water safe surfaces, while discouraging repeat marking. Safe around children and pets. Strong and Safe on Surfaces It Simply Works Simple Solution Stain and Odour Remover for Dogs is specially formulated for tough pet odours and stains, contains Enzymes that break down organic residue and the Pro Bacteria permanently eliminates stains and odours from carpets, upholstery or any other water Safe surface.