Buster Plughole Block Preventer 500mlUnique Diactive foam expands to fill the entire pipe, deep cleaning to prevent build up of gunge and trapped debris in plugholes, pipes & overflows. Suitable for kitchen and bathroom sinks, showers and baths. Use weekly, Deep cleans to protect against build up, Up to 8 doses Ingredients Block Preventer contains amongst other ingredients: <5% Chlorine based Bleaching Agents, Non Ionic Surfactants Perfumes, Benzyl 2 Hydroxybenzoate