This is a white granular powder which when added to water produces a solution which is ideal for unblocking drains and heavy duty cleaning unblocking drains or pipes sprinkle the contents of the pack into 5 litres of cold water and stir with a stick take care as product will heat up pour immediately and carefully down the drain or pipe after 20 30 minutes flush with boiling water repeat if necessary heavy duty cleaning use same method as above however use approx 125g of caustic per 5 litres